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
Apr 12, 2026Varnish Enterprise before 6.0.16r12 allows a "workspace overflow" denial of service (daemon panic) for shared VCL.CVE-2026-40395 · Other software · varnish-software · reported by MITREMedium 4
Varnish Enterprise before 6.0.16r12 allows a "workspace overflow" denial of service (daemon panic) for shared VCL. The headerplus.write_req0() function from vmod_headerplus updates the underlying req0, which is normally the original read-only request from which req is derived (readable and writable from VCL). This is useful in the active VCL, after amending req, to prepare a refined req0 before switching to a different VCL with the return (vcl(<label>)) action. This is for example how the Varnish Controller operates shared VCL deployments. If the amended req contained too many header fields for req0, this would have resulted in a workspace overflow that would in turn trigger a panic and crash the Varnish Enterprise server. This could be used as a Denial of Service attack vector by malicious clients.
- Product
- Varnish Enterprise
- What to do
- Apply the vendor’s update. The NVD record links to the advisory.
Full record and what to do →NVD recorddocs.varnish-software.com
Apr 12, 2026Varnish Cache 9 before 9.0.1 and Varnish Enterprise before 6.0.16r11 allows a "workspace overflow" denial of service (daemon panic) for certain amounts of prefeCVE-2026-40394 · Other software · varnish-software · reported by MITREMedium 4
Varnish Cache 9 before 9.0.1 and Varnish Enterprise before 6.0.16r11 allows a "workspace overflow" denial of service (daemon panic) for certain amounts of prefetched data. The setup of an HTTP/2 session starts with a speculative HTTP/1 transport, and upon upgrading to h2 the HTTP/1 request is repurposed as stream zero. During the upgrade, a buffer allocation is made to reserve space to send frames to the client. This allocation would split the original workspace, and depending on the amount of prefetched data, the next fetch could perform a pipelining operation that would run out of workspace.
- Product
- Varnish Cache
- What to do
- Apply the vendor’s update. The NVD record links to the advisory.
Full record and what to do →NVD recorddocs.varnish-software.com
Mar 27, 2026Varnish Cache before 8.0.1 and Varnish Enterprise before 6.0.16r12, in certain unchecked req.url scenarios, mishandle URLs with a path of / for HTTP/1.1, potentCVE-2026-34475 · Other software · varnish-software · reported by MITREMedium 5.4
Varnish Cache before 8.0.1 and Varnish Enterprise before 6.0.16r12, in certain unchecked req.url scenarios, mishandle URLs with a path of / for HTTP/1.1, potentially leading to cache poisoning or authentication bypass.
- Product
- Varnish Cache
- What to do
- Apply the vendor’s update. The NVD record links to the advisory.
May 13, 2025Varnish Cache before 7.6.3 and 7.7 before 7.7.1, and Varnish Enterprise before 6.0.13r14, allow client-side desync via HTTP/1 requests, because the product incoCVE-2025-47905 · Other software · varnish-software · reported by MITREMedium 5.4
Varnish Cache before 7.6.3 and 7.7 before 7.7.1, and Varnish Enterprise before 6.0.13r14, allow client-side desync via HTTP/1 requests, because the product incorrectly permits CRLF to be skipped to delimit chunk boundaries.
- Product
- Varnish Cache
- What to do
- Apply the vendor’s update. The NVD record links to the advisory.
Full record and what to do →NVD recordvarnish-cache.orgopenwall.com
Mar 21, 2025Varnish Enterprise before 6.0.13r13 allows remote attackers to obtain sensitive information via an out-of-bounds read for range requests on ephemeral MSE4 steveCVE-2025-30347 · Other software · varnish-software · reported by MITREMedium 4
Varnish Enterprise before 6.0.13r13 allows remote attackers to obtain sensitive information via an out-of-bounds read for range requests on ephemeral MSE4 stevedore objects.
- Product
- Varnish Enterprise
- What to do
- Apply the vendor’s update. The NVD record links to the advisory.
Full record and what to do →NVD recorddocs.varnish-software.com
Mar 21, 2025Varnish Cache before 7.6.2 and Varnish Enterprise before 6.0.13r10 allow client-side desync via HTTP/1 requests.CVE-2025-30346 · Other software · varnish-software · reported by MITREMedium 5.4
Varnish Cache before 7.6.2 and Varnish Enterprise before 6.0.13r10 allow client-side desync via HTTP/1 requests.
- Product
- Varnish Cache
- What to do
- Apply the vendor’s update. The NVD record links to the advisory.
Full record and what to do →NVD recordvarnish-cache.orglists.debian.org
Mar 23, 2024Varnish Cache before 7.3.2 and 7.4.x before 7.4.3 (and before 6.0.13 LTS), and Varnish Enterprise 6 before 6.0.12r6, allows credits exhaustion for an HTTP/2 conCVE-2024-30156 · Other software · reported by MITREHigh 7.5
Varnish Cache before 7.3.2 and 7.4.x before 7.4.3 (and before 6.0.13 LTS), and Varnish Enterprise 6 before 6.0.12r6, allows credits exhaustion for an HTTP/2 connection control flow window, aka a Broke Window Attack.
- What to do
- Apply the vendor’s update. The NVD record links to the advisory.
Full record and what to do →NVD recordvarnish-cache.orgvarnish-cache.org
Aug 23, 2023libvmod-digest before 1.0.3, as used in Varnish Enterprise 6.0.x before 6.0.11r5, has an out-of-bounds memory access during base64 decoding, leading to both autCVE-2023-41104 · Other software · libvmod_digest · reported by MITREMedium 6.5
libvmod-digest before 1.0.3, as used in Varnish Enterprise 6.0.x before 6.0.11r5, has an out-of-bounds memory access during base64 decoding, leading to both authentication bypass and information disclosure; however, the exact attack surface will depend on the particular VCL (Varnish Configuration Language) configuration in use.
- Product
- libvmod_digest
- What to do
- Apply the vendor’s update. The NVD record links to the advisory.
Full record and what to do →NVD recorddocs.varnish-software.comgithub.com
Jan 25, 2022In Varnish Cache before 6.6.2 and 7.x before 7.0.2, Varnish Cache 6.0 LTS before 6.0.10, and and Varnish Enterprise (Cache Plus) 4.1.x before 4.1.11r6 and 6.0.xCVE-2022-23959 · Other software · Varnish-software · reported by MITRECritical 9.1
In Varnish Cache before 6.6.2 and 7.x before 7.0.2, Varnish Cache 6.0 LTS before 6.0.10, and and Varnish Enterprise (Cache Plus) 4.1.x before 4.1.11r6 and 6.0.x before 6.0.9r4, request smuggling can occur for HTTP/1 connections.
- Product
- Varnich Cache
- What to do
- Apply the vendor’s update. The NVD record links to the advisory.
Full record and what to do →NVD recorddocs.varnish-software.comlists.debian.org
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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