{"id":"CVE-2026-33996","state":"PUBLISHED","title":"LibJWT has NULL/bounds validation in JWK octet and RSA PSS parsing","description":"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.","publishedAt":"2026-03-27T22:21:21.465Z","updatedAt":"2026-03-31T18:53:51.741Z","severity":{"score":5.8,"label":"Medium","version":"4.0","vector":"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","source":"GitHub_M"},"assigner":"GitHub_M","products":["benmcollins libjwt"],"affected":[{"vendor":"benmcollins","product":"libjwt","versions":[{"version":">= 3.0.0, < 3.3.0","status":"affected"}]}],"references":["https://github.com/benmcollins/libjwt/security/advisories/GHSA-ph96-hqpc-9f66","https://github.com/benmcollins/libjwt/commit/cfd890286fa49ae61b534c937c9f0428b5c6034c"],"weaknesses":["CWE-476"],"ingestedAt":"2026-10-29T20:11:40.391Z","source":{"repository":"CVEProject/cvelistV5","path":"cves/2026/33xxx/CVE-2026-33996.json","commit":"556c9d3a8cd17e218bb8e452ba7cd619a384ff47"},"raw":{"dataType":"CVE_RECORD","dataVersion":"5.2","cveMetadata":{"cveId":"CVE-2026-33996","state":"PUBLISHED","datePublished":"2026-03-27T22:21:21.465Z","dateUpdated":"2026-03-31T18:53:51.741Z","assignerShortName":"GitHub_M","assignerOrgId":"a0819718-46f1-4df5-94e2-005712e83aaa","dateReserved":"2026-03-24T22:20:06.214Z"},"containers":{"cna":{"title":"LibJWT has NULL/bounds validation in JWK octet and RSA PSS parsing","descriptions":[{"lang":"en","value":"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."}],"affected":[{"vendor":"benmcollins","product":"libjwt","versions":[{"version":">= 3.0.0, < 3.3.0","status":"affected"}]}],"references":[{"url":"https://github.com/benmcollins/libjwt/security/advisories/GHSA-ph96-hqpc-9f66","name":"https://github.com/benmcollins/libjwt/security/advisories/GHSA-ph96-hqpc-9f66","tags":["x_refsource_CONFIRM"]},{"url":"https://github.com/benmcollins/libjwt/commit/cfd890286fa49ae61b534c937c9f0428b5c6034c","name":"https://github.com/benmcollins/libjwt/commit/cfd890286fa49ae61b534c937c9f0428b5c6034c","tags":["x_refsource_MISC"]}],"metrics":[{"cvssV4_0":{"attackVector":"ADJACENT","attackComplexity":"HIGH","attackRequirements":"PRESENT","privilegesRequired":"NONE","userInteraction":"ACTIVE","vulnConfidentialityImpact":"LOW","vulnIntegrityImpact":"LOW","vulnAvailabilityImpact":"HIGH","subConfidentialityImpact":"LOW","subIntegrityImpact":"LOW","subAvailabilityImpact":"LOW","baseScore":5.8,"baseSeverity":"MEDIUM","vectorString":"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","version":"4.0"}}],"problemTypes":[{"descriptions":[{"cweId":"CWE-476","lang":"en","description":"CWE-476: NULL Pointer Dereference","type":"CWE"}]}],"providerMetadata":{"shortName":"GitHub_M","orgId":"a0819718-46f1-4df5-94e2-005712e83aaa","dateUpdated":"2026-03-27T22:21:21.465Z"},"source":{"advisory":"GHSA-ph96-hqpc-9f66","discovery":"UNKNOWN"}},"adp":[{"title":"CISA ADP Vulnrichment","metrics":[{"other":{"type":"ssvc","content":{"timestamp":"2026-03-31T18:50:38.575748Z","id":"CVE-2026-33996","options":[{"Exploitation":"none"},{"Automatable":"no"},{"Technical Impact":"partial"}],"role":"CISA Coordinator","version":"2.0.3"}}}],"providerMetadata":{"shortName":"CISA-ADP","orgId":"134c704f-9b21-4f2e-91b3-4a467353bcc0","dateUpdated":"2026-03-31T18:53:51.741Z"}}]}}}