{"basis":"claimed","id":"CVE-2026-33439","name":"Pre-Authentication Remote Code Execution via `jato.clientSession` Deserialization in OpenAM","vendorProject":"OpenIdentityPlatform","product":"OpenAM","publishedAt":"2026-04-07","cvss":{"score":9.3,"severity":"CRITICAL","version":"4.0"},"exploited":null,"epss":{"score":0.09333,"percentile":0.95384,"date":"2026-11-02"},"coverage":{"cloudflare":{"status":"none","firstOn":null,"daysToRule":null},"aws":{"status":"none","firstOn":null,"daysToRule":null},"azure":{"status":"none","firstOn":null,"daysToRule":null},"google":{"status":"none","firstOn":null,"daysToRule":null},"fastly":{"status":"no_history","firstOn":null,"daysToRule":null},"f5":{"status":"rule","firstOn":"2026-09-16","daysToRule":162},"akamai":{"status":"no_source","firstOn":null,"daysToRule":null},"crs":{"status":"none","firstOn":null,"daysToRule":null}},"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.","cwes":["CWE-502"],"vendors":[{"vendor":"cloudflare","status":"none","basis":"claimed","firstOn":null,"firstIsNew":false,"daysToRule":null,"daysAtMost":null,"freePlan":false,"claims":[]},{"vendor":"aws","status":"none","basis":"claimed","firstOn":null,"firstIsNew":false,"daysToRule":null,"daysAtMost":null,"freePlan":false,"claims":[]},{"vendor":"azure","status":"none","basis":"claimed","firstOn":null,"firstIsNew":false,"daysToRule":null,"daysAtMost":null,"freePlan":false,"claims":[]},{"vendor":"google","status":"none","basis":"claimed","firstOn":null,"firstIsNew":false,"daysToRule":null,"daysAtMost":null,"freePlan":false,"claims":[]},{"vendor":"fastly","status":"no_history","basis":"claimed","firstOn":null,"firstIsNew":false,"daysToRule":null,"daysAtMost":null,"freePlan":false,"claims":[]},{"vendor":"f5","status":"rule","basis":"claimed","firstOn":"2026-09-16","firstIsNew":true,"daysToRule":162,"daysAtMost":null,"freePlan":false,"claims":[{"id":"9afc54460a417fcb4288fbda7d066cad8ddec516458a06a620ed23f4095045e5","cve_id":"CVE-2026-33439","vendor":"f5","product":"Attack signatures","rule_id":"200204093","rule_name":"OpenAM Unauthenticated Remote Code Execution","change":"new","default_action":null,"published_on":"2026-09-16","source_url":"https://docs.cloud.f5.com/docs-v2/platform/changelogs/security-details-changelog","source_title":"F5 Distributed Cloud attack signatures changelog","excerpt":"Added: signature 200204093 \"OpenAM Unauthenticated Remote Code Execution\" (Server Side Code Injection, risk High), systems: Other Web Server. References: CVE-2026-33439.","first_seen_at":"2026-11-02T21:00:24.509Z"}]},{"vendor":"akamai","status":"no_source","basis":"claimed","firstOn":null,"firstIsNew":false,"daysToRule":null,"daysAtMost":null,"freePlan":false,"claims":[]},{"vendor":"crs","status":"none","basis":"claimed","firstOn":null,"firstIsNew":false,"daysToRule":null,"daysAtMost":null,"freePlan":false,"claims":[]}],"updatedAt":"2026-11-02T21:16:35.125Z","cvssVector":"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","ssvc":{"exploitation":"none","automatable":"yes","technicalImpact":"total"},"measured":[{"engineId":"owasp-crs","engineName":"OWASP Core Rule Set","engineVersion":"4.25.0","runtime":"Coraza v3.8.1","config":"paranoia level 1, anomaly threshold 5, default CRS settings","ranAt":"2026-11-02T22:32:39.000Z","verdict":"passed","templateId":"CVE-2026-33439","templatePath":"http/cves/2026/CVE-2026-33439.yaml","requests":1,"blockedRequests":0,"rules":[],"note":"","requestDetail":[{"method":"GET","path":"/openam/ui/PWResetUserValidation","status":200,"blocked":false,"rules":[]}]},{"engineId":"owasp-crs","engineName":"OWASP Core Rule Set","engineVersion":"4.25.0","runtime":"Coraza v3.8.1","config":"paranoia level 2, anomaly threshold 5, default CRS settings","ranAt":"2026-11-02T22:32:39.000Z","verdict":"passed","templateId":"CVE-2026-33439","templatePath":"http/cves/2026/CVE-2026-33439.yaml","requests":1,"blockedRequests":0,"rules":[],"note":"","requestDetail":[{"method":"GET","path":"/openam/ui/PWResetUserValidation","status":200,"blocked":false,"rules":[]}]}],"social":{"total":1,"first_seen":"2026-11-02T22:32:24.000Z","daily":[{"day":"2026-10-21","posts":0},{"day":"2026-10-22","posts":0},{"day":"2026-10-23","posts":0},{"day":"2026-10-24","posts":0},{"day":"2026-10-25","posts":0},{"day":"2026-10-26","posts":0},{"day":"2026-10-27","posts":0},{"day":"2026-10-28","posts":0},{"day":"2026-10-29","posts":0},{"day":"2026-10-30","posts":0},{"day":"2026-10-31","posts":0},{"day":"2026-11-01","posts":0},{"day":"2026-11-02","posts":1},{"day":"2026-11-03","posts":0}],"top_posts":[],"exploit_repositories":[{"source":"github","kind":"poc","url":"https://github.com/stapat1245/CVE-2026-33439_poc","author":"stapat1245","author_name":null,"avatar_url":"https://avatars.githubusercontent.com/u/85617297?v=4","text":"stapat1245/CVE-2026-33439_poc: Proof of Concept for CVE-2026-33439 RCE in OpenAM","engagement":1,"posted_at":"2026-11-02T22:32:24.000Z"}]}}