CVE-2026-33996 (GCVE-0-2026-33996)

Vulnerability from cvelistv5 – Published: 2026-03-27 22:21 – Updated: 2026-03-31 18:53
VLAI
Title
LibJWT has NULL/bounds validation in JWK octet and RSA PSS parsing
Summary
LibJWT is a C JSON Web Token Library. Starting in version 3.0.0 and prior to version 3.3.0, the JWK parsing for RSA-PSS did not protect against a NULL value when expecting to parse JSON string values. A specially crafted JWK file could exploit this behavior by using integers in places where the code expected a string. This was fixed in v3.3.0. A workaround is available. Users importing keys through a JWK file should not do so from untrusted sources. Use the `jwk2key` tool to check for validity of a JWK file. Likewise, if possible, do not use JWK files with RSA-PSS keys.
Severity
5.8 (Medium)
CVSS:4.0/AV:A/AC:H/AT:P/PR:N/UI:A/VC:L/VI:L/VA:H/SC:L/SI:L/SA:L
SSVC
Exploitation: none Automatable: no Technical Impact: partial
CISA Coordinator · CISA-ADP (v2.0.3)
Decision recorded 2026-03-31 18:50 UTC
CWE
  • CWE-476 - NULL Pointer Dereference
Assigner
GitHub_M CNA
References
Impacted products
Vendor Product Version
benmcollins libjwt Affected: >= 3.0.0, < 3.3.0
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