CVE-2026-33439
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.
INFO
Published Date :
April 7, 2026, 9:17 p.m.
Last Modified :
April 15, 2026, 11:34 p.m.
Remotely Exploit :
Yes !
Source :
[email protected]
CVSS Scores
| Score | Version | Severity | Vector | Exploitability Score | Impact Score | Source |
|---|---|---|---|---|---|---|
| CVSS 3.1 | CRITICAL | [email protected] | ||||
| CVSS 4.0 | CRITICAL | [email protected] |
Solution
- Update OpenAM to version 16.0.6.
- Apply vendor patches if available.
- Validate updated configurations.
- Monitor for suspicious activity.
Public PoC/Exploit Available at Github
CVE-2026-33439 has a 3 public
PoC/Exploit available at Github.
Go to the Public Exploits tab to see the list.
References to Advisories, Solutions, and Tools
Here, you will find a curated list of external links that provide in-depth
information, practical solutions, and valuable tools related to
CVE-2026-33439.
| URL | Resource |
|---|---|
| https://github.com/OpenIdentityPlatform/OpenAM/security/advisories/GHSA-2cqq-rpvq-g5qj | Exploit Vendor Advisory |
CWE - Common Weakness Enumeration
While CVE identifies
specific instances of vulnerabilities, CWE categorizes the common flaws or
weaknesses that can lead to vulnerabilities. CVE-2026-33439 is
associated with the following CWEs:
Common Attack Pattern Enumeration and Classification (CAPEC)
Common Attack Pattern Enumeration and Classification
(CAPEC)
stores attack patterns, which are descriptions of the common attributes and
approaches employed by adversaries to exploit the CVE-2026-33439
weaknesses.
We scan GitHub repositories to detect new proof-of-concept exploits. Following list is a collection of public exploits and proof-of-concepts, which have been published on GitHub (sorted by the most recently updated).
CVE-2026-33439
Shell Java
Vulnerable endpoint description for CVE-2026-33439 in OpenAM
爬取secwiki和xuanwu.github.io/sec.today,分析安全信息站点、安全趋势、提取安全工作者账号(twitter,weixin,github等)
Python HTML
Results are limited to the first 15 repositories due to potential performance issues.
The following list is the news that have been mention
CVE-2026-33439 vulnerability anywhere in the article.
-
Daily CyberSecurity
Critical Pre-Auth RCE Found in OpenAM Identity Platform
OpenAM, the widely-deployed open-source access management solution, is facing a critical security challenge following the discovery of a pre-authentication Remote Code Execution (RCE) vulnerability. T ... Read more
The following table lists the changes that have been made to the
CVE-2026-33439 vulnerability over time.
Vulnerability history details can be useful for understanding the evolution of a vulnerability, and for identifying the most recent changes that may impact the vulnerability's severity, exploitability, or other characteristics.
-
Initial Analysis by [email protected]
Apr. 15, 2026
Action Type Old Value New Value Added CVSS V3.1 AV:N/AC:L/PR:N/UI:N/S:U/C:H/I:H/A:H Added CPE Configuration OR *cpe:2.3:a:openidentityplatform:openam:*:*:*:*:*:*:*:* versions up to (excluding) 16.0.6 Added Reference Type GitHub, Inc.: https://github.com/OpenIdentityPlatform/OpenAM/security/advisories/GHSA-2cqq-rpvq-g5qj Types: Exploit, Vendor Advisory -
New CVE Received by [email protected]
Apr. 07, 2026
Action Type Old Value New Value Added 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. Added CVSS V4.0 AV:N/AC:L/AT:N/PR:N/UI:N/VC:H/VI:H/VA:H/SC:N/SI:N/SA:N/E:X/CR:X/IR:X/AR:X/MAV:X/MAC:X/MAT:X/MPR:X/MUI:X/MVC:X/MVI:X/MVA:X/MSC:X/MSI:X/MSA:X/S:X/AU:X/R:X/V:X/RE:X/U:X Added CWE CWE-502 Added Reference https://github.com/OpenIdentityPlatform/OpenAM/security/advisories/GHSA-2cqq-rpvq-g5qj