CVE-2026-33439 (GCVE-0-2026-33439)
Vulnerability from cvelistv5 – Published: 2026-04-07 20:46 – Updated: 2026-04-08 16:14
VLAI
EPSS
VEX
Title
Pre-Authentication Remote Code Execution via `jato.clientSession` Deserialization in OpenAM
Summary
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.
Severity
SSVC
Exploitation: none
Automatable: yes
Technical Impact: total
CISA Coordinator · CISA-ADP (v2.0.3)
Decision recorded 2026-04-08 16:11 UTC
CWE
- CWE-502 - Deserialization of Untrusted Data
Assigner
References
1 reference
| URL | Tags |
|---|---|
| https://github.com/OpenIdentityPlatform/OpenAM/se… | x_refsource_CONFIRM |
Impacted products
1 product
| Vendor | Product | Version | CPE status | |
|---|---|---|---|---|
| OpenIdentityPlatform | OpenAM |
Affected:
< 16.0.6
|
guessed |
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