SECURELYN

CVE-2026-102946

joserfc is a Python library that provides an implementation of several JSON Object Signing and Encryption (JOSE) standards. Prior to 1.7.4, joserfc.jws.deserialize_json() accepts a JWS General JSON Serialization with an empty signatures array as authenticated. The verify_general_json() loop performs no iterations for the empty array and returns success because no signature check failed, allowing an attacker without a signing key to supply an arbitrary payload that relying applications may treat as authentic. The issue affects the General JSON Serialization path; compact JWS and JWT decoding,…

Scores

9.1
CVSS 9.1 out of 10, critical severity.
0.1%
EPSS 0.1% chance of exploitation in the next 30 days.

The facts

Published
15 October 2026
Last changed
15 October 2026
NVD status
Deferred
Severity
Critical, CVSS 9.1 out of 10 (version 3.1)
CVSS:3.1/AV:N/AC:L/PR:N/UI:N/S:U/C:H/I:H/A:N
Weakness
Known exploited
Not in the CISA Known Exploited Vulnerabilities catalogue in this build.
EPSS
0.1% chance of exploitation activity in the next 30 days (percentile 2).

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References