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.
9 results
Mar 12, 2026Cap'n Proto is a data interchange format and capability-based RPC system.CVE-2026-32240 · Other software · capnproto · reported by GitHubMedium 6.3
Cap'n Proto is a data interchange format and capability-based RPC system. Prior to 1.4.0, when using Transfer-Encoding: chunked, if a chunk's size parsed to a value of 2^64 or larger, it would be truncated to a 64-bit integer. In theory, this bug could enable HTTP request/response smuggling. This vulnerability is fixed in 1.4.0.
- Product
- capnproto
- What to do
- Apply the vendor’s update. The NVD record links to the advisory.
Full record and what to do →NVD recordcapnproto.orgcapnproto.org
Mar 12, 2026Cap'n Proto is a data interchange format and capability-based RPC system.CVE-2026-32239 · Other software · capnproto · reported by GitHubMedium 6.3
Cap'n Proto is a data interchange format and capability-based RPC system. Prior to 1.4.0, a negative Content-Length value was converted to unsigned, treating it as an impossibly large length instead. In theory, this bug could enable HTTP request/response smuggling. This vulnerability is fixed in 1.4.0.
- Product
- capnproto
- What to do
- Apply the vendor’s update. The NVD record links to the advisory.
Full record and what to do →NVD recordcapnproto.orgcapnproto.org
Nov 21, 2023Cap'n Proto is a data interchange format and capability-based RPC system.CVE-2023-48230 · Other software · capnproto · reported by GitHubMedium 5.9
Cap'n Proto is a data interchange format and capability-based RPC system. In versions 1.0 and 1.0.1, when using the KJ HTTP library with WebSocket compression enabled, a buffer underrun can be caused by a remote peer. The underrun always writes a constant value that is not attacker-controlled, likely resulting in a crash, enabling a remote denial-of-service attack. Most Cap'n Proto and KJ users are unlikely to have this functionality enabled and so unlikely to be affected. Maintainers suspect only the Cloudflare Workers Runtime is affected. If KJ HTTP is used with WebSocket compression enabled, a malicious peer may be able to cause a buffer underrun on a heap-allocated buffer. KJ HTTP is an optional library bundled with Cap'n Proto, but is not directly used by Cap'n Proto. WebSocket compression is disabled by default. It must be enabled via a setting passed to the KJ HTTP library via `HttpClientSettings` or `HttpServerSettings`. The bytes written out-of-bounds are always a specific constant 4-byte string `{ 0x00, 0x00, 0xFF, 0xFF }`. Because this string is not controlled by the attacker, maintainers believe it is unlikely that remote code execution is possible. However, it cannot
- Product
- capnproto
- What to do
- Apply the vendor’s update. The NVD record links to the advisory.
Nov 30, 2022Cap'n Proto is a data interchange format and remote procedure call (RPC) system.CVE-2022-46149 · Other software · capnproto · reported by GitHubMedium 5.4
Cap'n Proto is a data interchange format and remote procedure call (RPC) system. Cap'n Proro prior to versions 0.7.1, 0.8.1, 0.9.2, and 0.10.3, as well as versions of Cap'n Proto's Rust implementation prior to 0.13.7, 0.14.11, and 0.15.2 are vulnerable to out-of-bounds read due to logic error handling list-of-list. This issue may lead someone to remotely segfault a peer by sending it a malicious message, if the victim performs certain actions on a list-of-pointer type. Exfiltration of memory is possible if the victim performs additional certain actions on a list-of-pointer type. To be vulnerable, an application must perform a specific sequence of actions, described in the GitHub Security Advisory. The bug is present in inlined code, therefore the fix will require rebuilding dependent applications. Cap'n Proto has C++ fixes available in versions 0.7.1, 0.8.1, 0.9.2, and 0.10.3. The `capnp` Rust crate has fixes available in versions 0.13.7, 0.14.11, and 0.15.2.
- Product
- capnproto
- What to do
- Apply the vendor’s update. The NVD record links to the advisory.
Aug 9, 2017Sandstorm Cap'n Proto before 0.4.1.1 and 0.5.x before 0.5.1.2, when an application invokes the totalSize method on an object reader, allows remote peers to causCVE-2015-2313 · Other software · Capnproto · reported by security@debian.orgHigh 7.5
Sandstorm Cap'n Proto before 0.4.1.1 and 0.5.x before 0.5.1.2, when an application invokes the totalSize method on an object reader, allows remote peers to cause a denial of service (CPU consumption) via a crafted small message, which triggers a "tight" for loop. NOTE: this vulnerability exists because of an incomplete fix for CVE-2015-2312.
- Product
- Capnproto
- What to do
- Apply the vendor’s update. The NVD record links to the advisory.
Full record and what to do →NVD recordopenwall.combugs.debian.org
Aug 9, 2017Sandstorm Cap'n Proto before 0.4.1.1 and 0.5.x before 0.5.1.1 allows remote peers to cause a denial of service (CPU and possibly general resource consumption) vCVE-2015-2312 · Other software · Capnproto · reported by security@debian.orgHigh 7.5
Sandstorm Cap'n Proto before 0.4.1.1 and 0.5.x before 0.5.1.1 allows remote peers to cause a denial of service (CPU and possibly general resource consumption) via a list with a large number of elements.
- Product
- Capnproto
- What to do
- Apply the vendor’s update. The NVD record links to the advisory.
Full record and what to do →NVD recordopenwall.combugs.debian.org
Aug 9, 2017Integer underflow in Sandstorm Cap'n Proto before 0.4.1.1 and 0.5.x before 0.5.1.1 might allow remote peers to cause a denial of service or possibly obtain sensCVE-2015-2311 · Other software · Capnproto · reported by security@debian.orgCritical 9.8
Integer underflow in Sandstorm Cap'n Proto before 0.4.1.1 and 0.5.x before 0.5.1.1 might allow remote peers to cause a denial of service or possibly obtain sensitive information from memory or execute arbitrary code via a crafted message.
- Product
- Capnproto
- What to do
- Apply the vendor’s update. The NVD record links to the advisory.
Full record and what to do →NVD recordopenwall.combugs.debian.org
Aug 9, 2017Integer overflow in layout.c++ in Sandstorm Cap'n Proto before 0.4.1.1 and 0.5.x before 0.5.1.1 allows remote peers to cause a denial of service or possibly obtCVE-2015-2310 · Other software · Capnproto · reported by security@debian.orgCritical 9.1
Integer overflow in layout.c++ in Sandstorm Cap'n Proto before 0.4.1.1 and 0.5.x before 0.5.1.1 allows remote peers to cause a denial of service or possibly obtain sensitive information from memory via a crafted message, related to pointer validation.
- Product
- Capnproto
- What to do
- Apply the vendor’s update. The NVD record links to the advisory.
Full record and what to do →NVD recordopenwall.combugs.debian.org
Apr 17, 2017Sandstorm Cap'n Proto before 0.5.3.1 allows remote crashes related to a compiler optimization.CVE-2017-7892 · Other software · Capnproto · reported by MITREHigh 7.5
Sandstorm Cap'n Proto before 0.5.3.1 allows remote crashes related to a compiler optimization. A remote attacker can trigger a segfault in a 32-bit libcapnp application because Cap'n Proto relies on pointer arithmetic calculations that overflow. An example compiler with optimization that elides a bounds check in such calculations is Apple LLVM version 8.1.0 (clang-802.0.41). The attack vector is a crafted far pointer within a message.
- Product
- Capnproto
- 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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