CVE-2026-48990

joserfc is a Python library that provides an implementation of several JSON Object Signing and Encryption (JOSE) standards. In versions 1.3.4 through 1.6.5, joserfc accepts oversized RFC7797 b64=false JWS payloads without applying JWSRegistry.max_payload_length, which can lead to resource exhaustion. The normal JWS compact and flattened JSON paths reject payloads above the configured payload-size limit with ExceededSizeError. The RFC7797 unencoded payload paths do not make the same check. A valid b64=false compact or flattened JSON JWS can therefore deserialize successfully with a payload larger than JWSRegistry.max_payload_length. Applications that accept lower-trust JWS values and rely on joserfc to reject oversized token content during verification have a moderate availability risk. This issue has been fixed in version 1.6.7.

CVSS v3 5.3 MEDIUM

5.3^/10

CVSS v3 : MEDIUM

Vector :

Exploitability : 3.9 / Impact : 1.4

Attack Vector NETWORK

Attack Complexity LOW

Privileges Required NONE

User Interaction NONE

Confidentiality Impact NONE

Integrity Impact NONE

Availability Impact LOW

Scope UNCHANGED

References

Link	Resource
https://github.com/authlib/joserfc/releases/tag/1.6.7
https://github.com/authlib/joserfc/security/advisories/GHSA-wphv-vfrh-23q5
https://github.com/authlib/joserfc/security/advisories/GHSA-wphv-vfrh-23q5

Configurations

No configuration.

History

18 Jun 2026, 14:17

Type	Values Removed	Values Added
New CVE

Information

Published : 2026-06-17 22:16

Updated : 2026-06-23 15:50

NVD link : CVE-2026-48990

Mitre link : CVE-2026-48990

CVE.ORG link : CVE-2026-48990

JSON object : View

Products Affected

No product.

CWE

CWE-400

Uncontrolled Resource Consumption

CWE-770

Allocation of Resources Without Limits or Throttling

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