CVE-2026-18500
HIGH
8,1
Source: ce714d77-add3-4f53-aff5-83d477b104bb
Attack Vector: network
Attack Complexity: low
Privileges Required: low
User Interaction: none
Scope: unchanged
Confidentiality: high
Integrity: high
Availability: none
Description
AI Translation Available
@fastify/jwt is a JSON Web Token plugin for Fastify. In versions before 10.2.2, a per-request verification key passed to request.jwtVerify({ key }) is silently overridden by the plugin's globally configured secret, because the option merge applies the global key last. Applications that use different keys for different authorization domains, for example separate user and admin keys, therefore accept a token signed with the global key on a route that explicitly requires another key. This lets an ordinary authenticated user cross a key-based trust boundary without knowing either secret. The issue is fixed in @fastify/jwt 10.2.2, where an explicit per-call key takes precedence over the global secret. Users should upgrade to 10.2.2.
347
Improper Verification of Cryptographic Signature
DraftCommon 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
https://cna.openjsf.org/security-advisories.html
https://github.com/fastify/fastify-jwt/security/advisories/GHSA-j4cx-787j-xjqg