6.5

CVE-2026-55955: apache software foundation apache tomcat Improper Authentication

CVSS: 6.5v3.1MediumAnalyzed
AliasesUBUNTU-CVE-2026-55955DEBIAN-CVE-2026-55955
Published 29-06-2026Last modified 30-06-2026
Open JSON

Vulnerability summary

CVE-2026-55955 is a medium (CVSS 6.5) Improper Authentication vulnerability in apache software foundation apache tomcat. EPSS estimates a 0.44% chance of exploitation in the next 30 days, higher than 36.4% of scored vulnerabilities.

Overall risk
26/100
0100
Medium · default modelHow is this calculated?
CVSS score
6.5/10
010
Medium · v3.1 (CVE.org)
EPSS score
0.44%
0%100%
Low · 0.00 pp in 30 days
KEVNot listedIn no KEV catalog
RansomwareNone recordedNo known use recorded
Public exploits0No public exploits recorded

Advisory lineage

Upstream 0 · Downstream 24 · Related 13
MGASA-2026-0323OPENSUSE-SU-2026:11195-1OPENSUSE-SU-2026:11208-1OPENSUSE-SU-2026:11209-1OPENSUSE-SU-2026:21327-1OPENSUSE-SU-2026:21328-1

Timeline

  1. 29-06-2026
    PublishedVulnerability first disclosed.
  2. 30-06-2026
    Last modifiedVulnerability information updated.

Description

Improper Authentication vulnerability in Apache Tomcat allowed a replay attack against the EncryptionInterceptor in the cluster component. This issue affects Apache Tomcat: from 11.0.0-M1 through 11.0.22, from 10.1.0-M1 through 10.1.55, from 9.0.13 through 9.0.18, from 8.5.38 through 8.5.100, from 7.0.100 through 7.0.109. Users are recommended to upgrade to version 11.0.23, 10.1.56, 9.0.119, which fixes the issue.

CVSS metrics

4 scores · 4 sources · 1 version

EPSS trend

Probability

0.44%

Chance of exploitation in the next 30 days

Percentile

36%

Versus all other CVEs

30-day change

0.00 pp

From 0.44% on 18-09-2026

18-09-202618-10-2026
EPSS score
0.44%

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) | < 11.0.24-1
  • tomcat9< 9.0.70-2
Apache1 product
  • tomcat< 9.0.119 | ≥ 10.1.0, < 10.1.56 | ≥ 11.0.0, < 11.0.23
Apache software foundation1 product
  • apache tomcat≥ 11.0.0-M1, ≤ 11.0.22 | ≥ 10.1.0-M1, ≤ 10.1.55 | ≥ 9.0.13, ≤ 9.0.118 | ≥ 8.5.38, ≤ 8.5.100 | ≥ 7.0.100, ≤ 7.0.109

4 vendors · 11 products

References

8 links