LibJWT has NULL/bounds validation in JWK octet and RSA PSS parsing
Summary
LibJWT has NULL/bounds validation in JWK octet and RSA PSS parsing
Original description
The description as published by the source.
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.
Source: OSV.dev (Open Source Vulnerabilities) NVD GitHub Advisory OSV
Fix status by distribution
Fixed packages published by each distribution for this CVE
- Debian DEBIAN-CVE-2026-33996 libjwt3 Fixed in: 3.3.2-1
- Ubuntu UBUNTU-CVE-2026-33996 libjwt
References
- advisory github.com
- advisory github.com
- advisory nvd.nist.gov
- patch github.com