9.8

CVE-2026-76183: apache software foundation apache tomcat Authentication Bypass by Alternate Name

CVSS: 9.8v3.1CriticalAwaiting analysis
AliasesUBUNTU-CVE-2026-76183DEBIAN-CVE-2026-76183
Published 23-09-2026Last modified 30-09-2026
Open JSON

Vulnerability summary

CVE-2026-76183 is a critical (CVSS 9.8) Authentication Bypass by Alternate Name vulnerability in apache software foundation apache tomcat. EPSS estimates a 0.39% chance of exploitation in the next 30 days, higher than 31.4% of scored vulnerabilities.

Overall risk
70/100
0100
High · default modelHow is this calculated?
CVSS score
9.8/10
010
Critical · v3.1 (CVE.org)
EPSS score
0.39%
0%100%
Low · Change unavailable
KEVNot listedIn no KEV catalog
RansomwareNone recordedNo known use recorded
Public exploits0No public exploits recorded

Advisory lineage

Upstream 0 · Downstream 10 · Related 7
MGASA-2026-0479OPENSUSE-SU-2026:11906-1OPENSUSE-SU-2026:11907-1OPENSUSE-SU-2026:11908-1OPENSUSE-SU-2026:21984-1RHSA-2026:68257

Timeline

  1. 23-09-2026
    PublishedVulnerability first disclosed.
  2. 30-09-2026
    Last modifiedVulnerability information updated.

Description

Authentication Bypass by Alternate Name vulnerability in Apache Tomcat allowed the security constraints for any WebSocket endpoint to be bypassed. This issue affects Apache Tomcat: from 11.0.0-M1 through 11.0.25, from 10.1.0-M1 through 10.1.59, from 9.0.0.M1 through 9.0.121. The following versions were EOS at the time the CVE was created but are known to be affected: from 8.5.0 through 8.5.100, from 7.0.43 through 7.0.109. Other unsupported versions may also be affected. Users are recommended to upgrade to version 11.0.26, 10.1.60 or 9.0.122, which fix the issue.

CVSS metrics

4 scores · 4 sources · 1 version

EPSS trend

Probability

0.39%

Chance of exploitation in the next 30 days

Percentile

31%

Versus all other CVEs

30-day change

Change unavailable

Change unavailable

24-09-202618-10-2026
EPSS score
0.39%

Known exploited

Compare KEV catalogs

Not in any of the 3 tracked catalogs.

Public exploits

0 found

No public exploits indexed.

Weaknesses

CWE · root cause

Affected systems

Ubuntu6 products
  • tomcat10All versions (No fix recorded)
  • tomcat11All versions (No fix recorded)
  • tomcat6All versions (No fix recorded)
  • tomcat7All versions (No fix recorded)
  • tomcat8All versions (No fix recorded)
Debian3 products
  • tomcat10All versions (No fix recorded) | < 10.1.60-1
  • tomcat11All versions (No fix recorded)
  • tomcat9< 9.0.70-2
Apache software foundation1 product
  • apache tomcat≥ 11.0.0-M1, ≤ 11.0.25 | ≥ 10.1.0-M1, ≤ 10.1.59 | ≥ 9.0.0.M1, ≤ 9.0.121 | ≥ 8.5.0, ≤ 8.5.100 | ≥ 7.0.43, ≤ 7.0.109

3 vendors · 10 products

References

8 links