CVE-2026-33439: Open Access Management (OpenAM) is an access management solution

Q: How do I fix CVE-2026-33439?

openam: upgrade to 16.0.6. Exact commands for each OS are on this page.

Q: Is CVE-2026-33439 being exploited?

CVE-2026-33439 is not on the CISA Known Exploited Vulnerabilities list at the time of the last update. Check again, as this can change.

Q: What does CVE-2026-33439 affect?

CVE-2026-33439 affects openam. Severity is critical (CVSS 9.8). 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 pa

Q: How urgent is CVE-2026-33439?

Priority 71/100. Critical severity; EPSS top 5%: very likely to be exploited; Public exploit reference; CISA SSVC: automatable with total technical impact; Remotely exploitable, no login, no user action

This week

CRITICAL 9.8REMOTEUPGRADE

CVE-2026-33439 is a critical-severity flaw (CVSS 9.8) affecting openam. Below: why it ranks where it does, which versions are affected, what to do, and the exact commands.

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 t

Why this priority

Critical severity
EPSS top 5%: very likely to be exploited
Public exploit reference
CISA SSVC: automatable with total technical impact
Remotely exploitable, no login, no user action

A fixed release or distro patch exists.

Risk facts

CVSS score	9.8 (Critical)
Attack vector	Network (remote)
Attack complexity	Low
Privileges needed	None
User interaction	None
EPSS exploit chance	9.3% (top 5%)
CISA exploited list	No
Weakness	CWE-502
Published	2026-04-07
Last modified	2026-07-24

Publisher (CNA): GitHub, Inc. · Vendor: openidentityplatform

Last updated 2026-07-24 · Sources: CVE Program, NVD, CISA KEV, EPSS and vendor advisories · How we score

Am I affected?

Timeline

2026-04-07 21:17 UTCPublished CVE record published
2026-07-24 23:10 UTCUpdated Record last modified

openidentityplatform openam UPGRADE

Affected: < 16.0.6

Fixed in: 16.0.6

Safe to downgrade to: no unaffected older release

1. Check installed version

apt-cache policy openam || rpm -q openam || openam --version

2. UPGRADE to 16.0.6 (Debian / Ubuntu)

sudo apt update && sudo apt install --only-upgrade openam

2. UPGRADE (RHEL / Amazon Linux / Fedora)

sudo dnf upgrade openam

Note

Distros often backport fixes without changing the version number. Confirm with the distro advisory or changelog.

Exact fixes by distribution

Maven · org.openidentityplatform.openam:openam · FIXED · 16.0.6 · vulnerable: <= 16.0.5 · source

Set org.openidentityplatform.openam:openam to 16.0.6 or later in pom.xml or build.gradle, then rebuild and redeploy.

Fedora 46 · python-googleapis-common-protos · FIXED · 1.75.5-1.fc46~bootstrap · FEDORA-2026-d911c4c4e6 · source

sudo dnf upgrade --advisory=FEDORA-2026-d911c4c4e6

Fedora ELN · see advisory · FIXED · FEDORA-2026-e3987c278f · source

sudo dnf upgrade --advisory=FEDORA-2026-e3987c278f

Public exploits and detection

Public code exists for this CVE. Treat unpatched systems as at risk, and only run PoCs in a lab.

GitHub PoC: TheMalwareGuardian/CVE-2026-33439 (11 stars)
GitHub PoC: infernosalex/CVE-2026-33439-Python-PoC (5 stars)
GitHub PoC: Ibonok/CVE-2026-33439-PoC (2 stars)
Write-up: github.com/OpenIdentityPlatform/OpenAM/security/advisories/GHSA-2cqq-rpvq-g5qj
Nuclei scan template: OpenAM <= 16.0.5 - Pre-Auth RCE via jato.clientSession Deserialization

Verify at the official source NVD · CVE Program · Report a problem with this page
Scores and fixes here are computed automatically from those and other public sources. Confirm with the vendor advisory before changing production systems.

Quick answers

How do I fix CVE-2026-33439?

openam: upgrade to 16.0.6. Exact commands for each OS are on this page.

Is CVE-2026-33439 being exploited?

CVE-2026-33439 is not on the CISA Known Exploited Vulnerabilities list at the time of the last update. Check again, as this can change.

What does CVE-2026-33439 affect?

CVE-2026-33439 affects openam. Severity is critical (CVSS 9.8). 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 pa

How urgent is CVE-2026-33439?

Priority 71/100. Critical severity; EPSS top 5%: very likely to be exploited; Public exploit reference; CISA SSVC: automatable with total technical impact; Remotely exploitable, no login, no user action

Software pages

Java vulnerabilities

References

← Back to latest CVEs