Vulnerability database
Every flaw the U.S. government’s cybersecurity agency (CISA) has confirmed attackers are using, plus the new WordPress plugin and theme bugs published each day, sorted by what they mean for a small business. We refresh it twice a day. If you see something your website or office runs, tell us.
182 results · page 1 of 4
Oct 30, 2026Improper Validation of Specified Quantity in Input vulnerability in the Elixir standard library's JSON module allows an unauthenticated attacker who supplies a CVE-2026-115274 · Other software · elixir-lang · reported by 6b3ad84c-e1a6-4bf7-a703-f496b71e49dbMedium 6.9
Improper Validation of Specified Quantity in Input vulnerability in the Elixir standard library's JSON module allows an unauthenticated attacker who supplies a JSON document to cause a denial of service through CPU and memory exhaustion. JSON.decode/1 and JSON.decode!/1 convert each integer literal with erlang:binary_to_integer/1 and do not bound its length. A literal of one million digits decodes successfully but costs 100 to 300 times as much CPU as a string of the same length, so one request body of a few megabytes holds a scheduler for about a second. A literal of more than about 1.29 million digits raises SystemLimitError. Applications generated by phx.new decode request bodies with JSON in Plug.Parsers, before routing and authentication. This issue affects elixir: from 1.18.0-rc.0 before 1.18.6, from 1.19.0-rc.0 before 1.19.7, and from 1.20.0-rc.0 before 1.20.5.
- Product
- elixir
- What to do
- Apply the vendor’s update. The NVD record links to the advisory.
Full record and what to do →NVD recordcna.erlef.orggithub.com
Oct 30, 2026Improper Validation of Specified Quantity in Input vulnerability in the Elixir standard library's URI module allows an attacker who supplies a URL to cause a deCVE-2026-109821 · Other software · elixir-lang · reported by 6b3ad84c-e1a6-4bf7-a703-f496b71e49dbMedium 6.3
Improper Validation of Specified Quantity in Input vulnerability in the Elixir standard library's URI module allows an attacker who supplies a URL to cause a denial of service through CPU exhaustion. URI.parse/1 converts the port component with String.to_integer/1 in split_authority/1 (lib/elixir/lib/uri.ex) without bounding its length, so a port of up to 1,262,592 decimal digits produces a bignum of that size and a longer one raises SystemLimitError. Rendering the parsed URI back to text (URI.to_string/1, inspect/1, logging, error formatting) converts the bignum with :erlang.integer_to_binary/1, which is quadratic on Erlang/OTP 27, 28 and 29.0: a 400,000-digit port renders in about 2.6 seconds and a 1 MB port in about 18 seconds. Ports above 65535 are also accepted. This issue affects elixir: from 0.5.0 before 1.18.6, from 1.19.0-rc.0 before 1.19.7, and from 1.20.0-rc.0 before 1.20.5.
- Product
- elixir
- What to do
- Apply the vendor’s update. The NVD record links to the advisory.
Full record and what to do →NVD recordcna.erlef.orggithub.com
Oct 28, 2026The DB Tools rely on the TLS implementation in Golang’s standard library, which generally uses the system CA store.CVE-2026-116641 · Other software · MongoDB · reported by cna@mongodb.comHigh 7.6
The DB Tools rely on the TLS implementation in Golang’s standard library, which generally uses the system CA store. However, the crypto/x509 package also has its own internal denylist of known-bad CA certificates. Golang 1.27.3 adds the eMudhra certificates to this list. DB Tools version 100.19.0 was compiled with Golang 1.26.8, which does not include this check. The issue is resolved by updating to Golang 1.27.3 in DB Tools 100.20.0
- Product
- Database Tools
- What to do
- Apply the vendor’s update. The NVD record links to the advisory.
Oct 27, 2026Use-after-free in the JavaScript: Standard Library component.CVE-2026-117872 · Computers, phones & browsers · Mozilla · reported by security@mozilla.org
Use-after-free in the JavaScript: Standard Library component. This vulnerability was fixed in Firefox 159, Firefox ESR 115.44, Firefox ESR 153.6, Thunderbird 159, and Thunderbird 153.6.
- Product
- Firefox
- What to do
- Apply the vendor’s update. The NVD record links to the advisory.
Full record and what to do →NVD recordbugzilla.mozilla.orgmozilla.org
Oct 20, 2026On most platforms, Go uses the given system root certificates.CVE-2026-111943 · Other software · Go standard library · reported by security@golang.orgMedium 6.8
On most platforms, Go uses the given system root certificates. However, in some narrower cases, the system trust stores may not be updated without further action. To defend against the narrower set of cases that may remain affected, a denylist was added in crypto/x509 to return an error when calling Verify with any of the known intermediate certificates that are no longer considered to be trustworthy.
- Product
- crypto/x509
- What to do
- Apply the vendor’s update. The NVD record links to the advisory.
Oct 8, 2026HTTP/2 servers could end up crashing due to inadvertently modifying its HPACK encoder concurrently.CVE-2026-97032 · Other software · Go standard library · reported by security@golang.orgHigh 7.5
HTTP/2 servers could end up crashing due to inadvertently modifying its HPACK encoder concurrently. This happens because the server modifies the HPACK encoder from two goroutines without synchronization: one uses the encoder to encode a HEADERS frame as part of a response sent to a client and the other modifies the encoder's table size when handling a SETTINGS frame containing SETTINGS_HEADER_TABLE_SIZE that a client sends. A malicious client can repeatedly send a request while changing the header table size to crash the server.
- Product
- net/http
- What to do
- Apply the vendor’s update. The NVD record links to the advisory.
Oct 8, 2026Multiple ECH outer extension references are not permitted under RFC 9849; previously, a client could send a well-crafted packet that could trigger memory exhausCVE-2026-97031 · Other software · Go standard library · reported by security@golang.orgHigh 7.5
Multiple ECH outer extension references are not permitted under RFC 9849; previously, a client could send a well-crafted packet that could trigger memory exhaustion in the server process by specifying multiple references. We now reject these as malformed and curb the memory amplification vector as a result.
- Product
- crypto/tls
- What to do
- Apply the vendor’s update. The NVD record links to the advisory.
Oct 8, 2026A trusted template author may have previously written a valid template wherein the use of the 'yield' keyword would not be correctly escaped.CVE-2026-97030 · Other software · Go standard library · reported by security@golang.orgMedium 6.1
A trusted template author may have previously written a valid template wherein the use of the 'yield' keyword would not be correctly escaped. We now ensure that valid keyword uses are escaped and non-keyword uses are not escaped.
- Product
- html/template
- What to do
- Apply the vendor’s update. The NVD record links to the advisory.
Oct 8, 2026When a JavaScript template literal contains consecutive expressions, the context tracking state was not properly reset upon entering a new expression.CVE-2026-94448 · Other software · Go standard library · reported by security@golang.orgMedium 6.1
When a JavaScript template literal contains consecutive expressions, the context tracking state was not properly reset upon entering a new expression. We now ensure that template-literal expression entries correctly reset context variables so all subsequent regular expression literals are accurately recognized and escaped.
- Product
- html/template
- What to do
- Apply the vendor’s update. The NVD record links to the advisory.
Oct 8, 2026Parsing a multipart form can bypass memory limits and read an arbitrarily long line into memory when the remaining limit at the start of a part is less than 400CVE-2026-94440 · Other software · Go standard library · reported by security@golang.orgHigh 7.5
Parsing a multipart form can bypass memory limits and read an arbitrarily long line into memory when the remaining limit at the start of a part is less than 400 bytes.
- Product
- net/textproto
- What to do
- Apply the vendor’s update. The NVD record links to the advisory.
Oct 8, 2026When an HTTP server handler sends a 2xx response to an HTTP/1 CONNECT request and returns without hijacking the connection, the server improperly continues to rCVE-2026-94439 · Other software · Go standard library · reported by security@golang.orgHigh 7.5
When an HTTP server handler sends a 2xx response to an HTTP/1 CONNECT request and returns without hijacking the connection, the server improperly continues to read and serve requests from the connection. Since a 2xx response to an HTTP/1 CONNECT converts the connection into a tunnel, the server should not treat the connection as continuing to contain HTTP. The impact of this misbehavior is mostly limited to potential request smuggling, where an intermediate proxy considers the data on the connection to be tunneled and the server considers it to be HTTP.
- Product
- net/http
- What to do
- Apply the vendor’s update. The NVD record links to the advisory.
Oct 8, 2026A malicious HTTP/2 peer can cause excessive CPU consumption in the client or server by opening a large number of streams and then sending many small SETTINGS frCVE-2026-78669 · Other software · Go standard library · reported by security@golang.orgHigh 7.5
A malicious HTTP/2 peer can cause excessive CPU consumption in the client or server by opening a large number of streams and then sending many small SETTINGS frames containing SETTINGS_INITIAL_WINDOW_SIZE values.
- Product
- net/http
- What to do
- Apply the vendor’s update. The NVD record links to the advisory.
Oct 8, 2026When parsing a Range header containing a large number of small ranges, FileServer(FS), ServeContent, and ServeFile(FS) can consume an excessive amount of CPU.CVE-2026-78667 · Other software · Go standard library · reported by security@golang.orgHigh 7.5
When parsing a Range header containing a large number of small ranges, FileServer(FS), ServeContent, and ServeFile(FS) can consume an excessive amount of CPU.
- Product
- net/http
- What to do
- Apply the vendor’s update. The NVD record links to the advisory.
Oct 8, 2026The HTTP/2 server can refund connection-level flow control twice for the same data: Once when a client resets a stream (refunding data for any sent-but-unread pCVE-2026-78663 · Other software · Go standard library · reported by security@golang.orgCritical 9.1
The HTTP/2 server can refund connection-level flow control twice for the same data: Once when a client resets a stream (refunding data for any sent-but-unread portion of the stream), and again when a request handler reads the buffered data. A malicious client can exploit this to bypass the configured connection-level flow control limit (MaxReceiveBufferPerConnection). Total buffered data is still limited by the concurrent stream limit and stream-level flow control.
- Product
- net/http
- What to do
- Apply the vendor’s update. The NVD record links to the advisory.
Oct 8, 2026Historically, we have been rather lax about malformed framing-related headers in our HTTP/2 implementation, as they cannot interfere with HTTP/2 framing.CVE-2026-78660 · Other software · Go standard library · reported by security@golang.orgHigh 7.5
Historically, we have been rather lax about malformed framing-related headers in our HTTP/2 implementation, as they cannot interfere with HTTP/2 framing. However, this makes it possible for our HTTP/2 implementation to forward responses containing such headers to an HTTP/1 client when acting as a reverse proxy. If the HTTP/1 client also does not behave strictly enough, this can result in response smuggling.
- Product
- net/http
- What to do
- Apply the vendor’s update. The NVD record links to the advisory.
Oct 8, 2026When "Trailer" headers are sent by a client, the HTTP server internally uses the header values to populate the Request.Trailer map passed to the server handler.CVE-2026-78659 · Other software · Go standard library · reported by security@golang.orgHigh 7.5
When "Trailer" headers are sent by a client, the HTTP server internally uses the header values to populate the Request.Trailer map passed to the server handler. Because Request.Trailer is a map, each entry incurs memory overhead. For HTTP/2 servers, a malicious client can exploit this by sending a "Trailer" header that declares a large number of fields, causing the server to allocate a disproportionate amount of memory while bypassing Server.MaxHeaderValueCount and Server.MaxHeaderBytes limits. This exploit is not applicable for HTTP/1 servers, which do not support multiplexing a large number of requests over one TCP connection, and whose Server.MaxHeaderBytes are calculated differently.
- Product
- net/http
- What to do
- Apply the vendor’s update. The NVD record links to the advisory.
Oct 8, 2026When http.Transport sends an HTTP/1 CONNECT request with a non-empty Request.Body, it writes the body directly to the connection without framing after the requeCVE-2026-56866 · Other software · Go standard library · reported by security@golang.orgHigh 7.5
When http.Transport sends an HTTP/1 CONNECT request with a non-empty Request.Body, it writes the body directly to the connection without framing after the request headers. If the server rejects the CONNECT request with a non-2xx keep-alive response, Transport returns the connection to the idle pool. Because CONNECT requests do not have a request body, the server may interpret the trailing body bytes as a subsequent pipelined HTTP/1.1 request on the connection, leaving the pooled connection desynchronized and causing the next caller that reuses it to read the response to the injected request. In reverse proxies (including httputil.ReverseProxy) that forward CONNECT requests through a shared Transport, this can lead to cross-user response poisoning.
- Product
- net/http
- What to do
- Apply the vendor’s update. The NVD record links to the advisory.
Oct 8, 2026On Windows, when the target of Root.Mkdir or Root.MkdirAll is a junction pointing to an empty location, the operation can create a directory at the junction tarCVE-2026-56857 · Other software · Go standard library · reported by security@golang.orgCritical 9.8
On Windows, when the target of Root.Mkdir or Root.MkdirAll is a junction pointing to an empty location, the operation can create a directory at the junction target even when that target is located outside the root. This only applies to operations where the last path component is a junction (path/to/junction, but not path/junction/target).
- Product
- os
- What to do
- Apply the vendor’s update. The NVD record links to the advisory.
Aug 28, 2026Uncontrolled Recursion vulnerability in the Elixir standard library allows an attacker who controls a list passed to inspect/1, List.to_string/1, or List.to_chaCVE-2026-75758 · Other software · elixir-lang · reported by 6b3ad84c-e1a6-4bf7-a703-f496b71e49dbMedium 5.9
Uncontrolled Recursion vulnerability in the Elixir standard library allows an attacker who controls a list passed to inspect/1, List.to_string/1, or List.to_charlist/1 to exhaust a BEAM node's memory. Inspect.List's charlist branch in lib/elixir/lib/inspect.ex classifies a list as a charlist using List.ascii_printable?/2, which examines only the first :printable_limit (4096 by default) elements, and then calls IO.chardata_to_string/1 on the whole term. A list whose printable prefix exceeds that limit but which contains a later element that is not a code point (an atom, an out-of-range integer, or an improper tail) is therefore mis-classified, and the conversion raises ArgumentError. That conversion runs inside List.to_string/1, whose rescue clause builds its message by interpolating inspect(list), which re-enters the same branch and raises again. The nested inspection is an argument to raise, so the recursion is not in tail position and every level is retained: the process stack grows monotonically while each cycle re-walks the list, until the process is killed by max_heap_size or, by default, the node runs out of memory. List.to_charlist/1 has the same rescue shape. Below the pr
- Product
- elixir
- What to do
- Apply the vendor’s update. The NVD record links to the advisory.
Full record and what to do →NVD recordcna.erlef.orggithub.com
Aug 13, 2026Handshake messages, such as KeyUpdate, are always considered as state-advancing, regardless of whether a handshake has been completed or not.CVE-2026-56862 · Other software · Go standard library · reported by security@golang.orgHigh 7.5
Handshake messages, such as KeyUpdate, are always considered as state-advancing, regardless of whether a handshake has been completed or not. As a result, a malicious client can keep sending KeyUpdate messages to force the server to keep performing key derivation operations indefinitely.
- Product
- crypto/tls
- What to do
- Apply the vendor’s update. The NVD record links to the advisory.
Aug 13, 2026Previously, resolving relative paths containing parent directory ('..') segments performed string conversions and buffer rewrites on each step, resulting in quaCVE-2026-56860 · Other software · Go standard library · reported by security@golang.orgMedium 5.9
Previously, resolving relative paths containing parent directory ('..') segments performed string conversions and buffer rewrites on each step, resulting in quadratic time complexity and high memory allocation overhead. Now, path resolution operates on a byte buffer using index-based backtracking for '..' segments, eliminating the quadratic time complexity and significantly reducing memory allocations.
- Product
- net/url
- What to do
- Apply the vendor’s update. The NVD record links to the advisory.
Aug 13, 2026Previously, DecodeElement would reset the depth counter causing it to never fire; this could lead to stack exhaustion.CVE-2026-56859 · Other software · Go standard library · reported by security@golang.orgHigh 7.5
Previously, DecodeElement would reset the depth counter causing it to never fire; this could lead to stack exhaustion.
- Product
- encoding/xml
- What to do
- Apply the vendor’s update. The NVD record links to the advisory.
Aug 13, 2026Previously, pathological inputs could close an unescaped '/' early, allowing for attack-controlled data to inject arbitrary content, potentially leading to XSS.CVE-2026-56858 · Other software · Go standard library · reported by security@golang.orgMedium 6.1
Previously, pathological inputs could close an unescaped '/' early, allowing for attack-controlled data to inject arbitrary content, potentially leading to XSS.
- Product
- html/template
- What to do
- Apply the vendor’s update. The NVD record links to the advisory.
Aug 13, 2026When a server is configured to support unencrypted HTTP/2, it reads a few bytes from each new connection to see if they contain the HTTP/2 client preface.CVE-2026-56853 · Other software · Go standard library · reported by security@golang.orgHigh 7.5
When a server is configured to support unencrypted HTTP/2, it reads a few bytes from each new connection to see if they contain the HTTP/2 client preface. ReadHeaderTimeout is unexpectedly not being applied when doing this.
- Product
- net/http
- What to do
- Apply the vendor’s update. The NVD record links to the advisory.
Aug 13, 2026Enforce a recursion limit in Unmarshal to prevent stack exhaustion when parsing deeply-nested, recursive structures.CVE-2026-33818 · Other software · Go standard library · reported by security@golang.orgHigh 7.5
Enforce a recursion limit in Unmarshal to prevent stack exhaustion when parsing deeply-nested, recursive structures.
- Product
- encoding/asn1
- What to do
- Apply the vendor’s update. The NVD record links to the advisory.
Jul 21, 2026Parsing an invalid SVCB or HTTPS RR can panic when the size of a parameter value overflows the message buffer.CVE-2026-46600 · Other software · Go standard library · reported by security@golang.orgHigh 7.5
Parsing an invalid SVCB or HTTPS RR can panic when the size of a parameter value overflows the message buffer.
- Product
- net
- What to do
- Apply the vendor’s update. The NVD record links to the advisory.
Jul 8, 2026Handshakes which used Encrypted Client Hello could be de-anonymized by a passive network observer due to a disclosure of pre-shared key identities in the unencrCVE-2026-42505 · Other software · Go standard library · reported by security@golang.orgMedium 5.3
Handshakes which used Encrypted Client Hello could be de-anonymized by a passive network observer due to a disclosure of pre-shared key identities in the unencrypted client hello.
- Product
- crypto/tls
- What to do
- Apply the vendor’s update. The NVD record links to the advisory.
Jul 8, 2026On Unix systems, opening a file in an os.Root improperly follows symlinks to locations outside of the Root when the final path component of the a path is a symbCVE-2026-39822 · Other software · Go standard library · reported by security@golang.orgHigh 7.8
On Unix systems, opening a file in an os.Root improperly follows symlinks to locations outside of the Root when the final path component of the a path is a symbolic link and the path ends in /. For example, 'root.Open("symlink/")' will open "symlink" even when "symlink" is a symbolic link pointing outside of the root.
- Product
- os
- What to do
- Apply the vendor’s update. The NVD record links to the advisory.
Jul 4, 2026Trail of Bits fickling versions up to and including 0.1.10 do not include the Python standard library modules _posixsubprocess, site, and atexit in the UNSAFE_ICVE-2026-14534 · Other software · trailofbits · reported by aa17e1a1-c329-4d6e-a1ed-8d0188aea082High 8.8
Trail of Bits fickling versions up to and including 0.1.10 do not include the Python standard library modules _posixsubprocess, site, and atexit in the UNSAFE_IMPORTS denylist (fickle.py). Because these modules are absent from the denylist, fickling's check_safety() function returns LIKELY_SAFE with zero findings for pickle payloads that invoke dangerous functions including _posixsubprocess.fork_exec (C-level process spawner capable of executing arbitrary binaries), site.execsitecustomize (executes arbitrary site customization code), and atexit._run_exitfuncs (triggers all registered exit handler callbacks). The fickling.load() API chains check_safety() into pickle.loads() as an explicit security gate; a LIKELY_SAFE verdict causes the payload to be deserialized and executed. This shares the same root cause as CVE-2026-22607 (cProfile), CVE-2025-67748 (pty), and CVE-2025-67747 (marshal/types). OvertlyBadEvals does not flag these modules because they are standard library imports. UnsafeImports does not flag them because they are not in the denylist. The UnusedVariables heuristic is defeated by the SETITEMS opcode pattern.
- Product
- fickling
- What to do
- Apply the vendor’s update. The NVD record links to the advisory.
Jun 23, 2026picklescan before 1.0.4 fails to block at least seven Python standard library modules (including uuid, _osx_support, _aix_support, _pyrepl.pager, and imaplib) eCVE-2026-56315 · Other software · picklescan · reported by VulnCheckCritical 9.3
picklescan before 1.0.4 fails to block at least seven Python standard library modules (including uuid, _osx_support, _aix_support, _pyrepl.pager, and imaplib) exposing eight functions that provide direct arbitrary command execution. Attackers can craft malicious pickle files importing these unblocked modules to achieve remote code execution while bypassing picklescan's safety validation entirely.
- Product
- picklescan
- What to do
- Apply the vendor’s update. The NVD record links to the advisory.
Full record and what to do →NVD recordgithub.comvulncheck.com
Jun 23, 2026Traefik before 2.10.5 and 3.0.0-beta4 is affected by a denial-of-service vulnerability in HTTP/2 request handling inherited from the Go standard library's HTTP/CVE-2023-54365 · Other software · Traefik · reported by VulnCheckHigh 8.7
Traefik before 2.10.5 and 3.0.0-beta4 is affected by a denial-of-service vulnerability in HTTP/2 request handling inherited from the Go standard library's HTTP/2 implementation (CVE-2023-44487 / CVE-2023-39325, the 'Rapid Reset' technique). A remote attacker can rapidly create and cancel HTTP/2 streams to exhaust server resources and cause service unavailability.
- Product
- Traefik
- What to do
- Apply the vendor’s update. The NVD record links to the advisory.
Full record and what to do →NVD recordgithub.comvulncheck.com
Jun 17, 2026PHP Standard Library (PSL) is set of APIs covering async, collections, networking, I/O, cryptography, terminal UI, etc.CVE-2026-48979 · Websites & servers · php-standard-library · reported by GitHubHigh 7.5
PHP Standard Library (PSL) is set of APIs covering async, collections, networking, I/O, cryptography, terminal UI, etc. In versions 6.1.0, 6.1.1 and 6.2.0, the Psl\H2\ServerConnection does not validate that the total bytes received in DATA frames match the content-length header declared in the HEADERS frame, allowing request smuggling. This is in violation of RFC 9113 §8.1.1. A malicious client is able to send more DATA bytes than declared, smuggling additional content past application-level size limits and send fewer DATA bytes than declared and close the stream early, causing applications that trust the declared length to behave incorrectly. The vulnerability is only reachable for consumers using Psl\H2\ServerConnection directly to accept untrusted client traffic. Consumers of documented high-level PSL APIs are not affected. This issue has been fixed in versions 6.1.2 and 6.2.1.
- Product
- php-standard-library
- What to do
- Apply the vendor’s update. The NVD record links to the advisory.
Jun 9, 2026Uncontrolled Resource Consumption vulnerability in the Elixir standard library's Version module allows an attacker who controls a version string to cause a deniCVE-2026-49762 · Other software · elixir-lang · reported by 6b3ad84c-e1a6-4bf7-a703-f496b71e49dbMedium 5.1
Uncontrolled Resource Consumption vulnerability in the Elixir standard library's Version module allows an attacker who controls a version string to cause a denial of service through CPU and memory exhaustion. The version parser converts numeric version components (major, minor, patch and numeric pre-release/build identifiers) to integers without bounding their length. A single large all-digit component therefore forces a super-linear, non-yielding base-10 to arbitrary-precision integer conversion (String.to_integer/1, i.e. :erlang.binary_to_integer/1) that pins a BEAM scheduler, and a larger component raises an uncaught SystemLimitError that crashes the calling process. A single moderately sized string (around one megabyte) is enough; no authentication is required. This is reachable from the public entry points Version.parse/1, Version.parse!/1, Version.match?/3, Version.compare/2, and Version.parse_requirement/1, which applications routinely call on untrusted input such as HTTP parameters, dependency-manifest fields, and package metadata. This vulnerability is associated with program files lib/version.ex and program routines 'Elixir.Version.Parser':parse_digits/2. This issue a
- Product
- elixir
- What to do
- Apply the vendor’s update. The NVD record links to the advisory.
Full record and what to do →NVD recordcna.erlef.orggithub.com
Jun 2, 2026When returning errors, functions in the net/textproto package would include its input as part of the error.CVE-2026-42507 · Other software · Go standard library · reported by security@golang.orgMedium 5.3
When returning errors, functions in the net/textproto package would include its input as part of the error. This might allow an attacker to inject misleading content to errors that are printed or logged.
- Product
- net/textproto
- What to do
- Apply the vendor’s update. The NVD record links to the advisory.
Jun 2, 2026Decoding a maliciously-crafted MIME header containing many invalid encoded-words can consume excessive CPU.CVE-2026-42504 · Other software · Go standard library · reported by security@golang.orgHigh 7.5
Decoding a maliciously-crafted MIME header containing many invalid encoded-words can consume excessive CPU.
- Product
- mime
- What to do
- Apply the vendor’s update. The NVD record links to the advisory.
Jun 2, 2026(*x509.Certificate).VerifyHostname previously called matchHostnames in a loop over all DNS Subject Alternative Name (SAN) entries.CVE-2026-27145 · Other software · Go standard library · reported by security@golang.orgMedium 6.5
(*x509.Certificate).VerifyHostname previously called matchHostnames in a loop over all DNS Subject Alternative Name (SAN) entries. This caused strings.Split(host, ".") to execute repeatedly on the same input hostname. With a large DNS SAN list, verification costs scaled quadratically based on the number of SAN entries multiplied by the hostname's label count. Because x509.Verify validates hostnames before building the certificate chain, this overhead occurred even for untrusted certificates.
- Product
- crypto/x509
- What to do
- Apply the vendor’s update. The NVD record links to the advisory.
May 22, 2026The ToASCII and ToUnicode functions incorrectly accept Punycode-encoded labels that decode to an ASCII-only label.CVE-2026-39821 · Other software · Go standard library · reported by security@golang.orgCritical 9.6
The ToASCII and ToUnicode functions incorrectly accept Punycode-encoded labels that decode to an ASCII-only label. For example, ToUnicode("xn--example-.com") incorrectly returns the name "example.com" rather than an error. This behavior can lead to privilege escalation in programs using the idna package. For example, a program which performs privilege checks on the ASCII hostname may reject "example.com" but permit "xn--example-.com". If that program subsequently converts the ASCII hostname to Unicode, it will inadvertently permits access to the Unicode name "example.com".
- Product
- net/http
- What to do
- Apply the vendor’s update. The NVD record links to the advisory.
May 7, 2026Pathological inputs could cause DoS through consumePhrase when parsing an email address according to RFC 5322.CVE-2026-42499 · Other software · Go standard library · reported by security@golang.orgHigh 7.5
Pathological inputs could cause DoS through consumePhrase when parsing an email address according to RFC 5322.
- Product
- net/mail
- What to do
- Apply the vendor’s update. The NVD record links to the advisory.
May 7, 2026The Dial and LookupPort functions panic on Windows when provided with an input containing a NUL (0).CVE-2026-39836 · Other software · Go standard library · reported by security@golang.orgHigh 7.5
The Dial and LookupPort functions panic on Windows when provided with an input containing a NUL (0).
- Product
- net
- What to do
- Apply the vendor’s update. The NVD record links to the advisory.
May 7, 2026If a trusted template author were to write a <script> tag containing an empty 'type' attribute or a 'type' attribute with an ASCII whitespace, the execution of CVE-2026-39826 · Other software · Go standard library · reported by security@golang.orgMedium 6.1
If a trusted template author were to write a <script> tag containing an empty 'type' attribute or a 'type' attribute with an ASCII whitespace, the execution of the template would incorrectly escape any data passed into the <script> block.
- Product
- html/template
- What to do
- Apply the vendor’s update. The NVD record links to the advisory.
May 7, 2026ReverseProxy can forward queries containing parameters not visible to Rewrite functions.CVE-2026-39825 · Other software · Go standard library · reported by security@golang.orgMedium 5.3
ReverseProxy can forward queries containing parameters not visible to Rewrite functions. When used with a Rewrite function, or a Director function which parses query parameters, ReverseProxy sanitizes the forwarded request to remove query parameters which are not parsed by url.ParseQuery. ReverseProxy does not take ParseQuery's limit on the total number of query parameters (controlled by GODEBUG=urlmaxqueryparams=N) into account. This can permit ReverseProxy to forward a request containing a query parameter that is not visible to the Rewrite function. For example, the query "a1=x&a2=x&...&a10000=x&hidden=y" can forward the parameter "hidden=y" while hiding it from the proxy's Rewrite function.
- Product
- net/http/httputil
- What to do
- Apply the vendor’s update. The NVD record links to the advisory.
May 7, 2026CVE-2026-27142 fixed a vulnerability in which URLs were not correctly escaped inside of a <meta> tag's <content> attribute.CVE-2026-39823 · Other software · Go standard library · reported by security@golang.orgMedium 6.1
CVE-2026-27142 fixed a vulnerability in which URLs were not correctly escaped inside of a <meta> tag's <content> attribute. If the URL content were to insert ASCII whitespaces around the '=' rune inside of the <content> attribute, the escaper would fail to similarly escape it, leading to XSS.
- Product
- html/template
- What to do
- Apply the vendor’s update. The NVD record links to the advisory.
May 7, 2026Well-crafted inputs reaching ParseAddress, ParseAddressList, and ParseDate were able to trigger excessive CPU exhaustion and memory allocations.CVE-2026-39820 · Other software · Go standard library · reported by security@golang.orgHigh 7.5
Well-crafted inputs reaching ParseAddress, ParseAddressList, and ParseDate were able to trigger excessive CPU exhaustion and memory allocations.
- Product
- net/mail
- What to do
- Apply the vendor’s update. The NVD record links to the advisory.
May 7, 2026When using LookupCNAME with the cgo DNS resolver, a very long CNAME response can trigger a double-free of C memory and a crash.CVE-2026-33811 · Other software · Go standard library · reported by security@golang.orgHigh 7.5
When using LookupCNAME with the cgo DNS resolver, a very long CNAME response can trigger a double-free of C memory and a crash.
- Product
- net
- What to do
- Apply the vendor’s update. The NVD record links to the advisory.
Apr 7, 2026When verifying a certificate chain containing excluded DNS constraints, these constraints are not correctly applied to wildcard DNS SANs which use a different cCVE-2026-33810 · Other software · Go standard library · reported by security@golang.orgHigh 8.2
When verifying a certificate chain containing excluded DNS constraints, these constraints are not correctly applied to wildcard DNS SANs which use a different case than the constraint. This only affects validation of otherwise trusted certificate chains, issued by a root CA in the VerifyOptions.Roots CertPool, or in the system certificate pool.
- Product
- crypto/x509
- What to do
- Apply the vendor’s update. The NVD record links to the advisory.
Apr 7, 2026Context was not properly tracked across template branches for JS template literals, leading to possibly incorrect escaping of content when branches were used.CVE-2026-32289 · Other software · Go standard library · reported by security@golang.orgMedium 6.1
Context was not properly tracked across template branches for JS template literals, leading to possibly incorrect escaping of content when branches were used. Additionally template actions within JS template literals did not properly track the brace depth, leading to incorrect escaping being applied. These issues could cause actions within JS template literals to be incorrectly or improperly escaped, leading to XSS vulnerabilities.
- Product
- html/template
- What to do
- Apply the vendor’s update. The NVD record links to the advisory.
Apr 7, 2026tar.Reader can allocate an unbounded amount of memory when reading a maliciously-crafted archive containing a large number of sparse regions encoded in the "oldCVE-2026-32288 · Other software · Go standard library · reported by security@golang.orgMedium 5.5
tar.Reader can allocate an unbounded amount of memory when reading a maliciously-crafted archive containing a large number of sparse regions encoded in the "old GNU sparse map" format.
- Product
- archive/tar
- What to do
- Apply the vendor’s update. The NVD record links to the advisory.
Apr 7, 2026If one side of the TLS connection sends multiple key update messages post-handshake in a single record, the connection can deadlock, causing uncontrolled consumCVE-2026-32283 · Other software · Go standard library · reported by security@golang.orgHigh 7.5
If one side of the TLS connection sends multiple key update messages post-handshake in a single record, the connection can deadlock, causing uncontrolled consumption of resources. This can lead to a denial of service. This only affects TLS 1.3.
- Product
- crypto/tls
- What to do
- Apply the vendor’s update. The NVD record links to the advisory.
Apr 7, 2026On Linux, if the target of Root.Chmod is replaced with a symlink while the chmod operation is in progress, Chmod can operate on the target of the symlink, even CVE-2026-32282 · Other software · Go standard library · reported by security@golang.orgMedium 6.4
On Linux, if the target of Root.Chmod is replaced with a symlink while the chmod operation is in progress, Chmod can operate on the target of the symlink, even when the target lies outside the root. The Linux fchmodat syscall silently ignores the AT_SYMLINK_NOFOLLOW flag, which Root.Chmod uses to avoid symlink traversal. Root.Chmod checks its target before acting and returns an error if the target is a symlink lying outside the root, so the impact is limited to cases where the target is replaced with a symlink between the check and operation.
- Product
- internal/syscall/unix
- What to do
- Apply the vendor’s update. The NVD record links to the advisory.
Apr 7, 2026Validating certificate chains which use policies is unexpectedly inefficient when certificates in the chain contain a very large number of policy mappings, possCVE-2026-32281 · Other software · Go standard library · reported by security@golang.orgHigh 7.5
Validating certificate chains which use policies is unexpectedly inefficient when certificates in the chain contain a very large number of policy mappings, possibly causing denial of service. This only affects validation of otherwise trusted certificate chains, issued by a root CA in the VerifyOptions.Roots CertPool, or in the system certificate pool.
- Product
- crypto/x509
- What to do
- Apply the vendor’s update. The NVD record links to the advisory.
Where this comes from: the exploited list is CISA’s Known Exploited Vulnerabilities catalog. Everything else is the whole National Vulnerability Database, where each record is published by the team that found the bug (Wordfence, Patchstack, WPScan, the vendors themselves and others); we show who. Exploit odds are FIRST’s EPSS, updated daily. Titles and categories are ours, so check the linked record before acting on a detail. For a write-up of the big ones, see our advisories. Every vendor, and every WordPress plugin and theme with a recorded flaw, also has its own page. All of it is free to reuse as JSON, CSV or RSS.
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