Vulnerability Intelligence Report
Pre-Authentication Remote Code Execution via `jato.clientSession` Deserialization in OpenAM
CVE-2026-33439
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.
Nuclei Template
CVSS Base Score
9.3
CRITICAL
EPSS Probability:10.49%
Executive Threat Verdict
Evaluating...
Evaluating Threat Landscape...
Assessing known weaponization, exploitation telemetry, and federal advisories.
Attack Surface
—
Authentication
—
Weaponization
—
SSVC Action
—
Weaknesses (CWE)
CWE-502 ↗CWE-502: Deserialization of Untrusted Data
Affected Products & Versions
| Vendor | Product | Affected Versions |
|---|---|---|
| OpenIdentityPlatform | OpenAM | < 16.0.6 (affected) |
References & Technical Advisories
No reference links found.
Threat Intelligence Signals
Identity & Timeline
| Status | PUBLISHED |
| Assigning Authority | GitHub, Inc. · Vendor · USA |
| Reserved | 2026-03-19T18:45:22 |
| Published | 2026-04-07T20:46:33 |
| Last Updated | 2026-04-08T16:14:49 |
Community Chatter & Buzz