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CVE-2026-35041

ReDoS in fast-jwt when using RegExp in allowed* leading to CPU exhaustion during token verification PUBLISHED

Description (CNA)

fast-jwt provides fast JSON Web Token (JWT) implementation. From 5.0.0 to 6.2.0, a denial-of-service condition exists in fast-jwt when the allowedAud verification option is configured using a regular expression. Because the aud claim is attacker-controlled and the library evaluates it against the supplied RegExp, a crafted JWT can trigger catastrophic backtracking in the JavaScript regex engine, resulting in significant CPU consumption during verification. This vulnerability is fixed in 6.2.1.

Affected (CNA)

Vendor / productVersions
nearform / fast-jwtaffected >= 5.0.0, < 6.2.1

CWE

CWE-1333

References

ADP enrichment

CISA-ADP

No English description supplied.