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CVE-2026-43513 (GCVE-0-2026-43513)

Vulnerability from cvelistv5 – Published: 2026-05-12 15:26 – Updated: 2026-05-14 19:53
VLAI
Title
Apache Tomcat: LockOutRealm treats user names as case-sensitive
Summary
Improper Handling of Case Sensitivity vulnerability in LockOutRealm in Apache Tomcat. This issue affects Apache Tomcat: from 11.0.0-M1 through 11.0.21, from 10.1.0-M1 through 10.1.54, from 9.0.0.M1 through 9.0.117, from 8.5.0 through 8.5.100, from 7.0.0 through 7.0.109. Older unsupported versions may also be affected. Users are recommended to upgrade to version 11.0.22, 10.1.55 or 9.0.118 which fix the issue.
Severity
7.5 (High)
CVSS:3.1/AV:N/AC:L/PR:N/UI:N/S:U/C:H/I:N/A:N
SSVC
Exploitation: none Automatable: yes Technical Impact: partial
CISA Coordinator · CISA-ADP (v2.0.3)
Decision recorded 2026-05-14 16:34 UTC
CWE
  • CWE-178 - Improper Handling of Case Sensitivity
Assigner
References
Impacted products
Vendor Product Version CPE status
Apache Software Foundation Apache Tomcat Affected: 11.0.0-M1 , ≤ 11.0.21 (semver)
Affected: 10.1.0-M1 , ≤ 10.1.54 (semver)
Affected: 9.0.0.M1 , ≤ 9.0.117 (semver)
Affected: 8.5.0 , ≤ 8.5.100 (semver)
Affected: 7.0.0 , ≤ 7.0.109 (semver)
Unknown: 0 , < 7.00 (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.

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  • 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.
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  • 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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