Authorization bypass through user-controlled key in YouTrack - CVE-2026-103491
Published: October 2, 2026
Vulnerability identifier: #VU153160
CSH Severity: Low
CVSS v4: 5.3 [CVSS:4.0/AV:N/AC:L/AT:N/PR:L/UI:N/VC:L/VI:N/VA:N/SC:N/SI:N/SA:N]
CVE-ID: CVE-2026-103491
CWE-ID: CWE-639
Exploitation vector: Remote access
Exploit availability:
No public exploit available
Vulnerability details
The vulnerability allows a remote user to disclose restricted issue information.
The vulnerability exists due to authorization bypass through user-controlled key in the issue activities API when handling requests for issue activities. A remote user can request activities for a restricted issue to disclose restricted issue information.
Affected software
YouTrack
How to mitigate CVE-2026-103491
Install security update from vendor's website.
YouTrack - update to 2026.2.19422