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.
Attack Parameters
Attack Vector
Network
Can be exploited remotely
Attack Complexity
High
Difficult to exploit
Privileges Required
None
No privileges needed
User Interaction
None
No user interaction needed
Impact Assessment
Confidentiality
High
Complete data leak
Integrity
High
Complete data modification
Availability
None
No disruption
CVSS Vector v3.1
Weakness Type (CWE)
Vulnerable Products 1
| Configuration | From (including) | Up to (excluding) |
|---|---|---|
|
Pyjwt_Project Pyjwt
cpe:2.3:a:pyjwt_project:pyjwt:2.13.0:*:*:*:*:*:*:*
|
— | — |
References 3
https://github.com/jpadilla/pyjwt/security/advisories/GHSA-w2cx-738m-mc7w
https://github.com/jpadilla/pyjwt/security/advisories/GHSA-w2cx-738m-mc7w
https://github.com/jpadilla/pyjwt/commit/801cd128528c62d9b23fcd161d1a2e1c17982f…
https://github.com/jpadilla/pyjwt/commit/801cd128528c62d9b23fcd161d1a2e1c17982f95
https://github.com/jpadilla/pyjwt/releases/tag/2.14.0
https://github.com/jpadilla/pyjwt/releases/tag/2.14.0