Critical (9.1) in doorkeeper project doorkeeper. EPSS 4.8% chance of exploitation in the next 30 days. Fixed in doorkeeper 4.2.0.
The Doorkeeper gem before 4.2.0 for Ruby might allow remote attackers to conduct replay attacks or revoke arbitrary tokens by leveraging failure to implement the OAuth 2.0 Token Revocation specification.
Severity
CVSS 3.0
9.1 critical
CVSS:3.0/AV:N/AC:L/PR:N/UI:N/S:U/C:N/I:H/A:H
EPSS
4.8% chance of exploitation in the next 30 days; higher than 91% of CVEs (scores of 2026-10-31)