9.1
CriticalCVSS 3.1 · from GitHub_M
CVE-2026-102946
joserfc: JWS signature verification bypass via empty signatures array in jws.deserialize_json
joserfc · CWE-290 · CWE-290Affectedjoserfc
FixNo fix listed yet.
PublishedOct 15, 18:28 · GitHub_M
ScoredOct 15 · 9.1 · GitHub_M
Exploit code publicNone known · checked 21:18 UTC
ExploitedNone known · CISA KEV checked 22:11 UTC
What we know
No known exploitation. CISA KEV, checked 22:11 UTC.
No public exploit code known. Exploit-DB, Metasploit, Nuclei, checked 21:18 UTC.
An attacker only needs network access to the target. No login needed. CVSS: network, no privileges.
A successful attack can read data and change data. CVSS impact.
A successful attack gives full control of the affected system. CISA: technical impact total.
Description
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, Flattened JSON serialization, and JWE JSON processing do not follow this vulnerable path. This issue is fixed in version 1.7.4.
From GitHub_M
Affected and fixed versions
ProductAffectedFixed injoserfc< 1.7.4–
Exploit code
Exploit-DBnone knownMetasploitnone knownNucleinone known