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Vulnerability record · CVE-2026-55955 · published 29 June 2026

CVE-2026-55955: Apache tomcat improper authentication vulnerability

Apache · Tomcat

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.

6.5 CVSS 3.1 Medium EPSS 0.44% · top 64.6% CWE-287 · Improper authentication
6.5CVSS 3.1 base score
0.44%EPSS exploitation probability, 30 days
NoNot in CISA KEV
1Affected product versions listed by NVD
2References
10 Jul 2026Last modified by NVD

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:3.1/AV:N/AC:L/PR:N/UI:N/S:U/C:L/I:L/A:N

Affected products

1 vulnerable configurations from NVD's CPE data, grouped by vendor and product.

References

LinkTags
https://lists.apache.org/thread/g4p5sf45p3f9r011pwqs9r54yd64s106 Mailing ListVendor Advisory
http://www.openwall.com/lists/oss-security/2026/06/29/24 Third Party Advisory

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Same products first, then exploited flaws of the same weakness class.

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Source: NIST National Vulnerability Database (record CVE-2026-55955), CISA KEV, FIRST EPSS (scores of 2026-09-28). This page is refreshed as NVD updates the record.