CVE-2026-48524
LOW
INFO
Priority: 0.01
BB Relevance:
57/100
Published: 2026-05-28
Modified: 2026-10-26
First seen: 2026-10-29
Status: active
Attack Surface
Network
No Auth
No Interaction
CVSS Vector Breakdown
AV:
Network
AC:
High
PR:
None
UI:
None
S:
Unchanged
C:
None
I:
None
A:
Low
Description
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.
Affected Software (1)
| Vendor | Product | Version |
|---|---|---|
| pyjwt_project | pyjwt | < 2.13.0 |
References & Advisories (1)
Mitigation
Vendor Advisory