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CVE-2026-55955 (GCVE-0-2026-55955)

Vulnerability from cvelistv5 – Published: 2026-06-29 20:44 – Updated: 2026-06-30 13:22
VLAI
Title
Apache Tomcat: EncryptInterceptor not protected against replay attacks
Summary
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.
Severity
6.5 (Medium)
CVSS:3.1/AV:N/AC:L/PR:N/UI:N/S:U/C:L/I:L/A:N
SSVC
Exploitation: none Automatable: no Technical Impact: partial
CISA Coordinator · CISA-ADP (v2.0.3)
Decision recorded 2026-06-30 13:21 UTC
CWE
  • CWE-287 - Improper Authentication
Assigner
References
Impacted products
Vendor Product Version CPE status
Apache Software Foundation Apache Tomcat Affected: 11.0.0-M1 , ≤ 11.0.22 (semver)
Affected: 10.1.0-M1 , ≤ 10.1.55 (semver)
Affected: 9.0.13 , ≤ 9.0.118 (semver)
Affected: 8.5.38 , ≤ 8.5.100 (semver)
Affected: 7.0.100 , ≤ 7.0.109 (semver)
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Forecast uses a logistic model when the trend is rising, or an exponential decay model when the trend is falling. Fitted via linearized least squares.

Sightings

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Nomenclature

  • Seen: The vulnerability was mentioned, discussed, or observed by the user.
  • Confirmed: The vulnerability has been validated from an analyst's perspective.
  • Published Proof of Concept: A public proof of concept is available for this vulnerability.
  • Exploited: The vulnerability was observed as exploited by the user who reported the sighting.
  • Patched: The vulnerability was observed as successfully patched by the user who reported the sighting.
  • Not exploited: The vulnerability was not observed as exploited by the user who reported the sighting.
  • Not confirmed: The user expressed doubt about the validity of the vulnerability.
  • Not patched: The vulnerability was not observed as successfully patched by the user who reported the sighting.


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