Dashboard / CVE-2026-62995

CVE-2026-62995

LOW
INFO Priority: 0.00 BB Relevance: 55/100
Published: 2026-07-29 Modified: 2026-10-24 First seen: 2026-10-29 Status: active

Attack Surface

Network Low Complexity No Interaction

CVSS Vector Breakdown

AV: Network
AC: Low
PR: Low
UI: None
S: X
AT: Present
VC: None
VI: Low
VA: None

Description

joserfc is a Python library that provides an implementation of several JSON Object Signing and Encryption (JOSE) standards. in versions 1.7.1 and prior, joserfc accepts JWTs with trailing padding (==) which are not conforming to the JOSE specifications. This leads to malleability of the JWTs when consumed by joserfc. Depending on this application this might or not be an issue. This could lead to bypass of token revocation or anti-replay protection when implemented as a deny list of tokens or a deny list of token hashes. Note that ECDSA JWS are always malleable because of the malleability of ECDSA signatures (first test case in the code bellow). This makes a scheme which assumes that JWTs are not malleable brittle. However for other signatures (or MAC) schemes it might make sense to assume non malleability of the token. This issue has been fixed in version 1.7.2.

Weakness Classification (1)

References & Advisories (1)

Bug Bounty Relevance

55 / 100
✓ Network accessible
✓ Low complexity
✓ No user interaction

CVSS Score

2.3 / 10.0 v4.0
CVSS:4.0/AV:N/AC:L/AT:P/PR:L/UI:N/VC:N/VI:L/VA:N/SC:N/SI:N/SA:N/E:X/CR:X/IR:X/AR:X/MAV:X/MAC:X/MAT:X/MPR:X/MUI:X/MVC:X/MVI:X/MVA:X/MSC:X/MSI:X/MSA:X/S:X/AU:X/R:X/V:X/RE:X/U:X

EPSS — Exploitation Probability

0.14%
Raw Score 0.001450
Percentile 3.7%
Date 2026-10-29

EPSS Trend

2026-10-29
0.00145
2026-10-28
0.00145

Intelligence Sources

nvd ref →

External Links