PT-2026-44396 · Jpadilla · Pyjwt

Published 2026-05-28 · Updated 2026-05-28 · CVE-2026-48524

NVD

CVSS v3.1

3.7

Low

Base vector

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

PyJWT is a JSON Web Token implementation in Python. Prior to 2.13.0, PyJWKClient.get signing key() forces a fresh HTTP request to the JWKS endpoint for every JWT with an unknown kid value, with no rate limiting. Since kid comes from the unverified token header, an attacker can trigger unlimited outbound requests. The vulnerability surfaces only when a JWKS fetch fails; an attacker can attempt to provoke that with sustained unknown-kid traffic, but the outcome depends on upstream JWKS-endpoint behavior (rate limiting, transient errors) which is beyond the attacker's control. This vulnerability is fixed in 2.13.0.

Fix

Improper Handling of Exceptional Conditions

Weakness Enumeration

CWE-460

CWE-755

Related Identifiers

CVE-2026-48524

Affected Products

Pyjwt

References · 2

• https://nvd.nist.gov/vuln/detail/CVE-2026-48524 · Security Note
• https://github.com/jpadilla/pyjwt/security/advisories/GHSA-fhv5-28vv-h8m8 · Note