Staging Environment: Content and features may be unstable or change without notice.
Advisory details: github_osv / GHSA-5mp6-jrq3-r938
Advisory ID github_osv/GHSA-5mp6-jrq3-r938
Aliases CVE-2026-43513
Summary Apache Tomcat: LockOutRealm treats user names as case-sensitive 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.
Status Published
Exploitability 0.5
Weighted Severity 6.8
Risk 3.4
Affected and Fixed Packages Package Details
Introduced and Fixed Package Commit Patches Package Commit Patches Details
Weaknesses (1)
No exploits are available.

No EPSS data available for this advisory.

Patch URL
There are no known patches.
Vector: CVSS:3.1/AV:N/AC:L/PR:N/UI:N/S:U/C:H/I:N/A:N Found at https://github.com/github/advisory-database/blob/main/advisories/github-reviewed/2026/05/GHSA-5mp6-jrq3-r938/GHSA-5mp6-jrq3-r938.json
Attack Vector (AV) Attack Complexity (AC) Privileges Required (PR) User Interaction (UI) Scope (S) Confidentiality Impact (C) Integrity Impact (I) Availability Impact (A)

network

adjacent_network

local

physical

low

high

none

low

high

none

required

unchanged

changed

high

low

none

high

low

none

high

low

none

Vector: SSVCv2/E:N/A:Y/T:P/P:M/B:A/M:M/D:T/2026-05-14T16:34:43Z/

Decision: Track

Source URL: https://github.com/cisagov/vulnrichment/blob/develop/2026/43xxx/CVE-2026-43513.json

Source Advisory: vulnrichment/CVE-2026-43513

View SSVC decision tree
[{'Exploitation': 'none'},
 {'Automatable': 'yes'},
 {'Technical Impact': 'partial'},
 {'Mission Prevalence': 'minimal'},
 {'Public Well-being Impact': 'material'},
 {'Mission & Well-being': 'medium'}]