CVE-2026-102273

PyJWT accepts public JWK containers as HMAC secrets

HIGH
7.4
CVSS Score
Published: September 28, 2026 at 08:38 PM UTC
Updated: October 6, 2026 at 06:29 PM UTC
2 products affected across 2 vendorsPyjwtPyjwt

Using pyjwt by jpadilla?

Get instant alerts when new vulnerabilities affect pyjwt - before attackers find them.

Real-time alertsTrack your software stackFree plan available
Severity
HIGH7.4
Exploit prediction
EPSS 0.2%
SSVC
No known exploit

Description

PyJWT is a Python implementation of JSON Web Token standards. From 2.13.0 until 2.14.0, PyJWT HMACAlgorithm.prepare_key is affected because HMAC key guard only recognizes top-level public JWK forms and misses container representations. This occurs when an application allows HMAC and asymmetric algorithms and passes a public JWK container as the raw key. As a result, public asymmetric key material is accepted as the HMAC secret. Consequently, an attacker who knows the public key can forge a token with arbitrary authenticated claims. This issue is fixed in version 2.14.0.

Affected

Our own answer: ranges merged, affected separated from platform-only, with confidence and review flags.

v < 2.14.0
Affected range stops below 2.14.0, so it looks safe — our inference, not a vendor statement

Remediation

No guide yet

No remediation guidance has been written for this CVE yet. What the record does show:

References (3)

x_refsource_CONFIRMVendor Advisory
Source: cverecord
https://github.com/jpadilla/pyjwt/security/advisories/GHSA-w2cx-738m-mc7w
x_refsource_MISCProductRelease Notes
Source: cverecord
https://github.com/jpadilla/pyjwt/releases/tag/2.14.0

SSVC — Action Prioritization

SSVCNo known exploitNot automatableTotal impact

SSVC signals action urgency (what to patch first), separate from CVSS which measures severity.

CVSS

7.4HIGHGitHub_M
Attack Vector
NETWORK
Complexity
HIGH
Privileges
NONE
User Interaction
NONE
Scope
UNCHANGED
Confidentiality
HIGH
Integrity
HIGH
Availability
NONE
Vector?

Quick Info

StatusANALYZED
CWE
CWE-347

Get alerted

Stop reading CVE feeds looking for your own stack

Track the products you run and VulnTracker tells you when a new CVE affects them — with what is known about fixing it, and nothing about the rest.

Free plan, no card