CVE-2026-33996

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.

CVSS v3 5.5 MEDIUM

5.5^/10

CVSS v3 : MEDIUM

Vector :

Exploitability : 1.8 / Impact : 3.6

Attack Vector LOCAL

Attack Complexity LOW

Privileges Required NONE

User Interaction REQUIRED

Confidentiality Impact NONE

Integrity Impact NONE

Availability Impact HIGH

Scope UNCHANGED

References

Link	Resource
https://github.com/benmcollins/libjwt/commit/cfd890286fa49ae61b534c937c9f0428b5c6034c	Patch
https://github.com/benmcollins/libjwt/security/advisories/GHSA-ph96-hqpc-9f66	Mitigation Vendor Advisory

Configurations

Configuration 1 (hide)

cpe:2.3:a:libjwt:libjwt:*:*:*:*:*:*:*:*

History

31 Mar 2026, 20:39

Type	Values Removed	Values Added
CPE		cpe:2.3:a:libjwt:libjwt::::::::
First Time		Libjwt libjwt Libjwt
CVSS	v2 : ~~unknown~~ v3 : ~~unknown~~	v2 : unknown v3 : 5.5
References	~~() https://github.com/benmcollins/libjwt/commit/cfd890286fa49ae61b534c937c9f0428b5c6034c -~~	() https://github.com/benmcollins/libjwt/commit/cfd890286fa49ae61b534c937c9f0428b5c6034c - Patch
References	~~() https://github.com/benmcollins/libjwt/security/advisories/GHSA-ph96-hqpc-9f66 -~~	() https://github.com/benmcollins/libjwt/security/advisories/GHSA-ph96-hqpc-9f66 - Mitigation, Vendor Advisory

27 Mar 2026, 23:17

Type	Values Removed	Values Added
New CVE

Information

Published : 2026-03-27 23:17

Updated : 2026-03-31 20:39

NVD link : CVE-2026-33996

Mitre link : CVE-2026-33996

CVE.ORG link : CVE-2026-33996

JSON object : View

Products Affected

libjwt

libjwt

CWE

CWE-476

NULL Pointer Dereference

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