CVE-2026-53431 Boruta accepts expired JWT client assertions due to missing exp claim validation

Authentication Bypass by Capture-replay vulnerability in malach-it Boruta allows an attacker who has obtained a previously valid JWT client assertion to authenticate as the issuing OAuth client after the assertion has expired. Boruta accepts JWT-based client authentication clientsecretjwt and...

EEF-CVE-2026-53431 Boruta accepts expired JWT client assertions due to missing exp claim validation

Summary Authentication Bypass by Capture-replay vulnerability in malach-it Boruta allows an attacker who has obtained a previously valid JWT client assertion to authenticate as the issuing OAuth client after the assertion has expired. Boruta accepts JWT-based client authentication client\secret\j...

CVE-2026-53431

Boruta (malach-it) Authentication Bypass via Capture-replay: from 2.3.0 before 2.3.7, JWT client assertions can be replayed after expiry because exp is not validated. Root causes: check_expiration only verifies presence of exp; token_config returns an empty map, so Joken’s exp validator is not en...