Vulnerability in Jetbrains Youtrack

CVE-2026-86478

In JetBrains YouTrack before 2025.3.161254, 2026.1.14042 improper authentication in YouTrack Helpdesk allowed unauthenticated account takeover via a self-asserted email address

Published · last modified .

CVSS v3 metric

CVSS v3 base score 9.8 (Critical). Vector: CVSS:3.1/AV:N/AC:L/PR:N/UI:N/S:U/C:H/I:H/A:H.

EPSS exploit prediction

EPSS: 0.006 (48.3th percentile), scored .

Very low probability of exploitation in the next 30 days; routine patching cadence is appropriate. 48th percentile — 48.3% of CVEs in the catalogue have a lower EPSS than this one. How to read EPSS.

EPSS trend (30 days)EPSS over the last 30 days for CVE-2026-86478: held from 0.004 to 0.006.

EPSS over last 30 days · oldest: 0.004 · newest: 0.006 · change: +0.002

Affected products

Weakness classification (CWE)

Public proof-of-concept exploits

References

Frequently asked questions

What is CVE-2026-86478?
CVE-2026-86478 is a critical-severity vulnerability in Jetbrains Youtrack, classified under Authentication Bypass by Spoofing. CVSS score: 9.8/10. Published 2026-09-07.
How severe is CVE-2026-86478?
Critical severity. CVSS v3 base score is 9.8 out of 10.
Is CVE-2026-86478 known to be exploited?
2 public proof-of-concept repositories are indexed. Not currently listed in the CISA KEV catalog.