{"id":"CVE-2026-33439","state":"PUBLISHED","title":"Pre-Authentication Remote Code Execution via `jato.clientSession` Deserialization in OpenAM","description":"Open Access Management (OpenAM) is an access management solution. Prior to 16.0.6, OpenIdentityPlatform OpenAM is vulnerable to pre-authentication Remote Code Execution (RCE) via unsafe Java deserialization of the jato.clientSession HTTP parameter. This bypasses the WhitelistObjectInputStream mitigation that was applied to the jato.pageSession parameter after CVE-2021-35464. An unauthenticated attacker can achieve arbitrary command execution on the server by sending a crafted serialized Java object as the jato.clientSession GET/POST parameter to any JATO ViewBean endpoint whose JSP contains <jato:form> tags (e.g., the Password Reset pages). This vulnerability is fixed in 16.0.6.","publishedAt":"2026-04-07T20:46:33.739Z","updatedAt":"2026-04-08T16:14:49.293Z","severity":{"score":9.3,"label":"Critical","version":"4.0","vector":"CVSS:4.0/AV:N/AC:L/AT:N/PR:N/UI:N/VC:H/VI:H/VA:H/SC:N/SI:N/SA:N","source":"GitHub_M"},"assigner":"GitHub_M","products":["OpenIdentityPlatform OpenAM"],"affected":[{"vendor":"OpenIdentityPlatform","product":"OpenAM","versions":[{"version":"< 16.0.6","status":"affected"}]}],"references":["https://github.com/OpenIdentityPlatform/OpenAM/security/advisories/GHSA-2cqq-rpvq-g5qj"],"weaknesses":["CWE-502"],"ingestedAt":"2026-10-29T20:11:40.391Z","source":{"repository":"CVEProject/cvelistV5","path":"cves/2026/33xxx/CVE-2026-33439.json","commit":"556c9d3a8cd17e218bb8e452ba7cd619a384ff47"},"raw":{"dataType":"CVE_RECORD","dataVersion":"5.2","cveMetadata":{"cveId":"CVE-2026-33439","state":"PUBLISHED","datePublished":"2026-04-07T20:46:33.739Z","dateUpdated":"2026-04-08T16:14:49.293Z","assignerShortName":"GitHub_M","assignerOrgId":"a0819718-46f1-4df5-94e2-005712e83aaa","dateReserved":"2026-03-19T18:45:22.438Z"},"containers":{"cna":{"title":"Pre-Authentication Remote Code Execution via `jato.clientSession` Deserialization in OpenAM","descriptions":[{"lang":"en","value":"Open Access Management (OpenAM) is an access management solution. Prior to 16.0.6, OpenIdentityPlatform OpenAM is vulnerable to pre-authentication Remote Code Execution (RCE) via unsafe Java deserialization of the jato.clientSession HTTP parameter. This bypasses the WhitelistObjectInputStream mitigation that was applied to the jato.pageSession parameter after CVE-2021-35464. An unauthenticated attacker can achieve arbitrary command execution on the server by sending a crafted serialized Java object as the jato.clientSession GET/POST parameter to any JATO ViewBean endpoint whose JSP contains <jato:form> tags (e.g., the Password Reset pages). This vulnerability is fixed in 16.0.6."}],"affected":[{"vendor":"OpenIdentityPlatform","product":"OpenAM","versions":[{"version":"< 16.0.6","status":"affected"}]}],"references":[{"url":"https://github.com/OpenIdentityPlatform/OpenAM/security/advisories/GHSA-2cqq-rpvq-g5qj","name":"https://github.com/OpenIdentityPlatform/OpenAM/security/advisories/GHSA-2cqq-rpvq-g5qj","tags":["x_refsource_CONFIRM"]}],"metrics":[{"cvssV4_0":{"attackVector":"NETWORK","attackComplexity":"LOW","attackRequirements":"NONE","privilegesRequired":"NONE","userInteraction":"NONE","vulnConfidentialityImpact":"HIGH","vulnIntegrityImpact":"HIGH","vulnAvailabilityImpact":"HIGH","subConfidentialityImpact":"NONE","subIntegrityImpact":"NONE","subAvailabilityImpact":"NONE","baseScore":9.3,"baseSeverity":"CRITICAL","vectorString":"CVSS:4.0/AV:N/AC:L/AT:N/PR:N/UI:N/VC:H/VI:H/VA:H/SC:N/SI:N/SA:N","version":"4.0"}}],"problemTypes":[{"descriptions":[{"cweId":"CWE-502","lang":"en","description":"CWE-502: Deserialization of Untrusted Data","type":"CWE"}]}],"providerMetadata":{"shortName":"GitHub_M","orgId":"a0819718-46f1-4df5-94e2-005712e83aaa","dateUpdated":"2026-04-07T20:46:33.739Z"},"source":{"advisory":"GHSA-2cqq-rpvq-g5qj","discovery":"UNKNOWN"}},"adp":[{"title":"CISA ADP Vulnrichment","metrics":[{"other":{"type":"ssvc","content":{"timestamp":"2026-04-08T16:11:05.727049Z","id":"CVE-2026-33439","options":[{"Exploitation":"none"},{"Automatable":"yes"},{"Technical Impact":"total"}],"role":"CISA Coordinator","version":"2.0.3"}}}],"providerMetadata":{"shortName":"CISA-ADP","orgId":"134c704f-9b21-4f2e-91b3-4a467353bcc0","dateUpdated":"2026-04-08T16:14:49.293Z"}}]}}}