Dashboard / CVE-2026-35040

CVE-2026-35040

MEDIUM
MEDIUM Priority: 0.02 BB Relevance: 71/100
Published: 2026-04-09 Modified: 2026-10-26 First seen: 2026-10-29 Status: active

Attack Surface

Network Low Complexity No Auth No Interaction

CVSS Vector Breakdown

AV: Network
AC: Low
PR: None
UI: None
S: Unchanged
C: None
I: None
A: Low

Description

fast-jwt provides fast JSON Web Token (JWT) implementation. Prior to 6.2.1, using certain modifiers on RegExp objects in the allowedAud, allowedIss, allowedSub, allowedJti, or allowedNonce options in verify functions can cause certain unintended behaviours. This is because some modifiers are stateful and will cause failures in every second verification attempt regardless of the validity of the token provided. Such modifiers are /g (global matching) and /y (sticky matching). This does NOT allow invalid tokens to be accepted, only for valid tokens to be improperly rejected in some configurations. Instead it causes 50% of valid authentication requests to fail in an alternating pattern. This vulnerability is fixed in 6.2.1.

Weakness Classification (2)

Affected Software (1)

VendorProductVersion
nearform fast-jwt < 6.2.1

References & Advisories (4)

Bug Bounty Relevance

71 / 100
✓ Network accessible
✓ No authentication
✓ Low complexity
✓ No user interaction

CVSS Score

5.3 / 10.0 v3.1
CVSS:3.1/AV:N/AC:L/PR:N/UI:N/S:U/C:N/I:N/A:L

EPSS — Exploitation Probability

0.38%
Raw Score 0.003830
Percentile 32.3%
Date 2026-10-29

EPSS Trend

2026-10-29
0.00383
2026-10-28
0.00383

Intelligence Sources

nvd ref →

External Links