CVE-2026-76183: Tomcat7 · Authentication Bypass by Alternate Name vulnerability in Apache Tomcat allowed the security
Affects tomcat7Source GCVE Database
Not known to be exploited · CVSS 9.8 Critical · fixed in 11.0.26 : patch tomcat7 as a priority.
Data as of 5 Nov 2026, 12:51 UTC
- Patch
- Available – fixed in 11.0.26
CVSS:3.1/AV:N/AC:L/PR:N/UI:N/S:U/C:H/I:H/A:HExploitation evidence
Disclosed: evidence found.
CVE published 23 Sep 2026
Detectable: no evidence on record.
No public nuclei template indexed
Weaponized: no evidence on record.
No public exploit code indexed in Metasploit or Exploit-DB
Exploited in the wildExploited: no evidence on record.
Not in CISA KEV and no source reports exploitation
Observed by OffSeq MirageSeen by Mirage: no evidence on record.
No attack traffic recorded by OffSeq Mirage sensors
A missing step is not evidence of safety. Sources: cve.org (opens in a new tab), the Metasploit, Exploit-DB and nuclei-templates index as of 5 Nov 2026.
What to do
Affected software
| Product | Affected | Fixed in |
|---|---|---|
Ubuntu 26.10tomcat10pkg:deb/ubuntu/tomcat10?arch=source&distro=stonkingOther threats | Affected
| Fixed in– |
Ubuntu 26.10tomcat11pkg:deb/ubuntu/tomcat11?arch=source&distro=stonkingOther threats | Affected
| Fixed in– |
Ubuntu 26.10tomcat9pkg:deb/ubuntu/tomcat9?arch=source&distro=stonkingOther threats | Affected
| Fixed in– |
Ubuntu 26.04 LTStomcat10pkg:deb/ubuntu/tomcat10?arch=source&distro=resoluteOther threats | Affected
| Fixed in– |
Ubuntu 26.04 LTStomcat9pkg:deb/ubuntu/tomcat9?arch=source&distro=resoluteOther threats | Affected
| Fixed in– |
Ubuntu 26.04 LTStomcat11pkg:deb/ubuntu/tomcat11?arch=source&distro=resoluteOther threats | Affected
| Fixed in– |
Check your own hosts for these packages with threat-finder (opens in a new tab), our free open-source scanner.
AI-suggested
Users should upgrade affected Apache Tomcat instances to versions 11.0.26, 10.1.60, or 9.0.122, which contain fixes for this vulnerability. No other mitigations or workarounds are indicated. Applying the official patches is the recommended and effective remediation.
Description
An authentication bypass vulnerability in Apache Tomcat affects multiple versions and allows security constraints on WebSocket endpoints to be bypassed. This critical vulnerability impacts Tomcat versions from 7.0.43 through 7.0.109, 8.5.0 through 8.5.100, 9.0.0.M1 through 9.0.121, 10.1.0-M1 through 10.1.59, and 11.0.0-M1 through 11.0.25. The issue is fixed in versions 11.0.26, 10.1.60, and 9.0.122. Users are advised to upgrade to these fixed versions to mitigate the risk.
References
- ubuntu.com/security/CVE-2026-76183 (opens in a new tab)
- cve.org/CVERecord?id=CVE-2026-76183 (opens in a new tab)
- github.com/apache/tomcat/commit/e182d86b7d4cc19ec4c24c38f37acc004404fe8e (opens in a new tab)
- github.com/apache/tomcat/commit/5b48790abd13d94c2bd351027a39a671916b5ddf (opens in a new tab)
- github.com/apache/tomcat/commit/a93a60a33f4cc202542eb6a0b87b7142d7db311c (opens in a new tab)
- lists.apache.org/thread/45mxk8nj2q8pkhct6lfxkvtm2jpywrsp (opens in a new tab)
- openwall.com/lists/oss-security/2026/09/23/21 (opens in a new tab)