QwikSec

Security Database

CVE

CWE

Training

CVE-2026-35039

Published: Apr 6, 2026

Modified: May 13, 2026

PUBLISHED

CVSS v3.1

9.1

CRITICAL

Description

fast-jwt provides fast JSON Web Token (JWT) implementation. From 0.0.1 to before 6.2.0, setting up a custom cacheKeyBuilder method which does not properly create unique keys for different tokens can lead to cache collisions. This could cause tokens to be mis-identified during the verification process leading to valid tokens returning claims from different valid tokens and users being mis-identified as other users based on the wrong token. Version 6.2.0 contains a patch.

Vendor	Product	Versions
nearform	fast-jwt	affected `>= 0.0.1, < 6.2.0`

Weaknesses (CWE)

CVSS v3.1 Details

CVSS v3.1 Vector

CVSS:3.1/AV:N/AC:L/PR:N/UI:N/S:U/C:H/I:H/A:N

Attack Vector

Network

Attack Complexity

Low

Privileges Required

None

User Interaction

None

Scope

Unchanged

Confidentiality

High

Integrity

High

Availability

None

References

https://github.com/nearform/fast-jwt/security/advisories/GHSA-rp9m-7r4c-75qg

x_refsource_CONFIRM

https://github.com/nearform/fast-jwt/commit/de121056c6415b58770c60640881eaec67ac4ceb

x_refsource_MISC

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