Authentication Bypass by Spoofing in YouTrack - CVE-2026-86478
Published: September 7, 2026
Vulnerability identifier: #VU147338
CSH Severity: High
CVSS v4: 9.3 [CVSS:4.0/AV:N/AC:L/AT:N/PR:N/UI:N/VC:H/VI:H/VA:N/SC:N/SI:N/SA:N]
CVE-ID: CVE-2026-86478
CWE-ID: CWE-290
Exploitation vector: Remote access
Exploit availability:
No public exploit available
Vulnerability details
The vulnerability allows a remote attacker to take over accounts.
The vulnerability exists due to improper authentication in YouTrack Helpdesk when processing a self-asserted email address. A remote attacker can provide a self-asserted email address to take over accounts.
Affected software
YouTrack
How to mitigate CVE-2026-86478
Install security update from vendor's website.
YouTrack - addressed in versions 2025.3.161254, 2026.1.14042