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.
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History
Thu, 18 Jun 2026 19:45:00 +0000
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Authlib
Authlib joserfc |
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Authlib
Authlib joserfc |
Thu, 18 Jun 2026 16:45:00 +0000
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ssvc
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Thu, 18 Jun 2026 04:45:00 +0000
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| Description | 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. | |
| Title | joserfc: b64=false RFC7797 JWS payloads bypass JWSRegistry payload-size limits during deserialization | |
| Weaknesses | CWE-400 CWE-770 |
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| References |
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| Metrics |
cvssV3_1
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Status: PUBLISHED
Assigner: GitHub_M
Published:
Updated: 2026-06-18T12:51:59.900Z
Reserved: 2026-05-26T23:26:07.975Z
Link: CVE-2026-48990
Updated: 2026-06-18T12:51:36.906Z
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OpenCVE Enrichment
Updated: 2026-06-18T19:30:15Z