CVE-2026-107724

Published: Ott 09, 2026 Last Modified: Ott 09, 2026
ExploitDB:
Other exploit source:
Google Dorks:
HIGH 7,4
Attack Vector: network
Attack Complexity: high
Privileges Required: none
User Interaction: none
Scope: unchanged
Confidentiality: high
Integrity: high
Availability: none

Description

AI Translation Available

fast-jwt provides fast JSON Web Token (JWT) implementation. In 6.2.4, fast-jwt can classify raw serialized public JWK or JWKS JSON as an HMAC secret because src/crypto.js performDetectPublicKeyAlgorithms treats non-PEM strings as symmetric key material. If HS256 is explicitly allowed or inferred, an attacker who knows the exact serialized public-key bytes can use those bytes as an HMAC key and create a token containing arbitrary claims that createVerifier accepts. Serialization ordering or whitespace differences can prevent exploitation, and applications using supported PEM keys with an asymmetric-only algorithm allowlist are not affected. This issue is fixed in version 6.3.0.

EPSS (Exploit Prediction Scoring System)

Trend Analysis

EPSS (Exploit Prediction Scoring System)

Prevede la probabilità di sfruttamento basata su intelligence sulle minacce e sulle caratteristiche della vulnerabilità.

EPSS Score
0,0022
Percentile
0,1th
Updated

EPSS Score Trend (Last 3 Days)

347

Improper Verification of Cryptographic Signature

Draft
Common Consequences
Security Scopes Affected:
Access Control Integrity Confidentiality
Potential Impacts:
Gain Privileges Or Assume Identity Modify Application Data Execute Unauthorized Code Or Commands
Applicable Platforms
All platforms may be affected
View CWE Details
https://github.com/nearform/fast-jwt/security/advisories/GHSA-g3jj-5cmm-3hxx
https://github.com/nearform/fast-jwt/commit/10f9591349199ed2ab9fa1748ce92cdca69…
https://github.com/nearform/fast-jwt/pull/636
https://github.com/nearform/fast-jwt/releases/tag/v6.3.0
https://github.com/nearform/fast-jwt/security/advisories/GHSA-g3jj-5cmm-3hxx