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 tags (e.g., the Password Reset pages). This vulnerability is fixed in 16.0.6.
CVE-2026-33439
“—” beside the score: it is equal to NVD's CVSS score.
This critical-severity CVE scores 9.8 under NVD CVSS v3. EPSS exploit probability: 9.3% (95th percentile of EPSS-scored CVEs). No GitHub Security Advisory CVSS is on record for this CVE.
Also known asEUVD-2026-19941 (ENISA EUVD)Source: ENISA EUVD
- Public exploit or proof-of-concept code is available
A fix is available — apply it.
- CVSS v3
- 9.8
- EG Score
- 9.8CRITICALmedium confidence
- EG Risk
- 75EG Risk 75/100
EG Risk is EchelonGraph's 0–100 priority score. It fuses impact severity (EG Severity, the CVSS base score, never the KEV-floored or EPSS-lifted EG Score) with real-world exploitation and automatability, under weights EchelonGraph set by hand, so you can rank equal-severity CVEs and fix the most dangerous first. Higher = act sooner.
How it’s computed (value × EchelonGraph’s weight)Severity98% × 45%Impact severity (EG Severity): CVSS 9.8 of 10. Never the KEV-floored or EPSS-lifted EG Score.Exploitation40% × 40%EchelonGraph's fixed weight for EG-KEV Tier 3 (Elevated): a constant, not a probability.Automatability100% × 15%CISA's SSVC Automatable value: yes (Vulnrichment).SSVC (CISA's decision table, applied by EchelonGraph): Track at low or medium mission impact; Attend at high (mission-essential systems).Exploitation none (CISA Vulnrichment) · Automatable yes (CISA Vulnrichment) · Technical impact total (CISA Vulnrichment). All three are CISA's SSVC values (Vulnrichment). EchelonGraph applied CISA's decision table to them; CISA publishes SSVC inputs and the table, not a decision for each CVE.Action: A fix is available. Apply it within your standard update timelines at low or medium mission impact and sooner than that at high. - EPSS PROB
- 9.3%
- EPSS %ILE
- 95th
- KEV
- Not listed
What the EG score is made of (scorer v4.0: the three questions the 0–10 score mixes, published apart · methodology)
The EG score (9.8): severity, escalated by confirmed exploitation. This CVE's 9.8 is its impact severity (EG Severity), not escalated.
- EG Severity
- 9.8 CRITICALCVSS-B, impact only: no KEV listing, EPSS or EG-KEV tier raises it.NVD CVSS v3 · CVSS v3.0 or v3.1
- EG Likelihood
- 9.3% within 30 daysSource: FIRST EPSS (model v2026.06.15, score date 2026-10-29). FIRST's exploitation probability, not an EchelonGraph model.
- Confirmed exploitation
- None on record (CISA KEV, EG-KEV Tier 1)Reported apart from the likelihood: an observed fact, not a probability.
- EG Priority
- SSVC Track at medium mission impactTrack at low or medium mission impact; Attend at high (mission-essential systems).CISA BOD 26-04: 3 days if the affected system is publicly exposed; 60 days if it is not.Each input and its source: the SSVC and BOD 26-04 blocks below.
SSVC (CISA's decision table, applied by EchelonGraph)Track at low or medium mission impact; Attend at high (mission-essential systems).
A fix is available. Apply it within your standard update timelines at low or medium mission impact and sooner than that at high.
Exploitation none (CISA Vulnrichment) · Automatable yes (CISA Vulnrichment) · Technical impact total (CISA Vulnrichment). All three are CISA's SSVC values (Vulnrichment). EchelonGraph applied CISA's decision table to them; CISA publishes SSVC inputs and the table, not a decision for each CVE. Mission impact is CISA's Mission & Well-being decision point, and only you can judge it. CISA's table makes it high when Mission Prevalence is Essential — the vulnerable component "directly provides capabilities that constitute at least one MEF for at least one entity" (MEF: mission essential function) — or when Public Well-Being Impact is Irreversible: "multiple fatalities are likely", the cyber-physical system "is likely lost or destroyed", "extreme or serious externalities" are imposed on other parties, or social systems such as elections or the financial grid "are destabilized and potentially collapse". CISA's decision table
BOD 26-04 (CISA's remediation timeline, Table 1)3 days if the affected system is publicly exposed; 60 days if it is not.
In CISA KEV no (CISA's KEV catalog) · Automatable yes (CISA Vulnrichment) · Technical impact total (CISA Vulnrichment). Whether your system is publicly exposed is yours to answer. BOD 26-04 binds US Federal Civilian Executive Branch agencies; for anyone else it is CISA's published timeline, a reference rather than an obligation. The directive · how EchelonGraph applies it
Published
April 7, 2026
Last Modified
July 24, 2026
Advisory Details (1)
Auto-updated Oct 17, 2026Pre-Authentication Remote Code Execution via `jato.clientSession` Deserialization in OpenAM · Advisory · OpenIdentityPlatform/OpenAM · GitHub
https://github.com/OpenIdentityPlatform/OpenAM/security/advisories/GHSA-2cqq-rpvq-g5qjAffected Packages
(1 across 1 ecosystem)
Maven(1)
| Package | Vulnerable range | Fix by version range | Dependents |
|---|---|---|---|
| org.openidentityplatform.openam:openam | 14.5.2 ... 16.0.5 (38 versions) |
| — |
Weakness Classification(1)
MITRE Common Weakness Enumeration — the root-cause categories this CVE belongs to.
Data Freshness Timeline
(refreshed 15× in last 7d / 52× in last 30d)
Each row is a time one of our pipelines fetched, updated or re-scored this CVE. For example, "NVD update" means NVD published or revised its analysis for this CVE; "MITRE cvelistV5" means we ingested or refreshed it from the CNA feed. An arrow marks a change the record states ("CVSS v3 → 9.1"); EPSS and GHSA rows show the values recorded at that time, not what changed (EPSS values are rounded; hover one for the exact figures). Most recent first.
Showing the most recent 96 of 205 refreshes on record for this CVE.
A repeat, a row identical to one the same pipeline wrote less than 10 seconds earlier, is not a separate refresh and is not counted. 4 repeat rows among the latest 100 are merged into the row they repeat. The 109 oldest rows on record are not shown and were not checked, so the counts can still include repeats.
- 2026-10-30 12:39 UTCEG score recompute
- 2026-10-29 16:33 UTCEPSS rescoreEPSS 9.3% · 95th percentile
- 2026-10-29 14:29 UTCEG score recompute
- 2026-10-28 16:32 UTCEPSS rescoreEPSS 9.3% · 95th percentile
- 2026-10-27 18:13 UTCEG score recompute
- 2026-10-27 16:31 UTCEPSS rescoreEPSS 9.3% · 95th percentile
- 2026-10-26 20:05 UTCEG score recompute
- 2026-10-26 16:31 UTCEPSS rescoreEPSS 9.3% · 95th percentile
- 2026-10-25 20:00 UTCEG score recompute
- 2026-10-25 16:32 UTCEPSS rescoreEPSS 9.3% · 95th percentile
- 2026-10-25 14:34 UTCEG score recompute
- 2026-10-24 21:52 UTCEG score recompute
- 2026-10-24 16:32 UTCEPSS rescoreEPSS 8.4% · 94th percentile
- 2026-10-23 23:44 UTCEG score recompute
- 2026-10-23 16:31 UTCEPSS rescoreEPSS 8.4% · 94th percentile
- 2026-10-23 01:17 UTCEG score recompute
- 2026-10-22 16:34 UTCEPSS rescoreEPSS 8.4% · 94th percentile
- 2026-10-22 02:23 UTCEG score recompute
- 2026-10-21 16:32 UTCEPSS rescoreEPSS 8.4% · 94th percentile
- 2026-10-21 04:13 UTCEG score recompute
- 2026-10-20 16:33 UTCEPSS rescoreEPSS 8.4% · 94th percentile
- 2026-10-20 06:00 UTCEG score recompute
- 2026-10-19 16:31 UTCEPSS rescoreEPSS 8.4% · 94th percentile
- 2026-10-19 07:49 UTCEG score recompute
- 2026-10-18 16:31 UTCEPSS rescoreEPSS 8.4% · 94th percentile
Show 71 moreShow fewer
- 2026-10-18 03:46 UTCEG score recompute
- 2026-10-17 16:34 UTCEPSS rescoreEPSS 8.4% · 94th percentile
- 2026-10-17 06:22 UTCEG score recompute
- 2026-10-16 16:41 UTCEPSS rescoreEPSS 8.4% · 94th percentile
- 2026-10-16 07:43 UTCEG score recompute
- 2026-10-15 16:32 UTCEPSS rescoreEPSS 8.4% · 94th percentile
- 2026-10-15 06:40 UTCEG score recompute
- 2026-10-14 16:32 UTCEPSS rescoreEPSS 8.4% · 94th percentile
- 2026-10-14 02:21 UTCEG score recompute
- 2026-10-13 16:34 UTCEPSS rescoreEPSS 8.4% · 94th percentile
- 2026-10-12 22:38 UTCEG score recompute
- 2026-10-12 16:34 UTCEPSS rescoreEPSS 8.4% · 94th percentile
- 2026-10-12 16:13 UTCEG score recompute
- 2026-10-11 19:55 UTCEG score recompute
- 2026-10-11 17:09 UTCEG score recompute
- 2026-10-11 14:36 UTCEG score recompute
- 2026-10-11 13:48 UTCEPSS rescoreEPSS 8.4% · 94th percentile
- 2026-10-11 12:16 UTCOSV refresh
- 2026-10-10 20:00 UTCEPSS rescoreEPSS 8.4% · 94th percentile
- 2026-10-09 20:07 UTCEPSS rescoreEPSS 8.4% · 94th percentile
- 2026-10-08 17:12 UTCEPSS rescoreEPSS 8.4% · 94th percentile
- 2026-10-07 23:47 UTCEPSS rescoreEPSS 8.4% · 94th percentile
- 2026-10-06 15:17 UTCEPSS rescoreEPSS 8.4% · 94th percentile
- 2026-10-05 17:42 UTCEPSS rescoreEPSS 8.4% · 94th percentile
- 2026-10-03 14:25 UTCEPSS rescoreEPSS 8.4% · 94th percentile
- 2026-10-01 19:49 UTCEPSS rescoreEPSS 8.4% · 94th percentile
- 2026-09-30 15:03 UTCEPSS rescoreEPSS 8.4% · 94th percentile
- 2026-09-28 13:51 UTCEPSS rescoreEPSS 8.4% · 94th percentile
- 2026-09-27 13:48 UTCEPSS rescoreEPSS 8.4% · 94th percentile
- 2026-09-26 15:58 UTCEPSS rescoreEPSS 8.4% · 94th percentile
- 2026-09-26 00:26 UTCEPSS rescoreEPSS 8.4% · 94th percentile
- 2026-09-22 00:15 UTCOSV refresh
- 2026-09-20 20:15 UTCEPSS rescoreEPSS 10% · 95th percentile
- 2026-09-18 19:28 UTCEPSS rescoreEPSS 10% · 95th percentile
- 2026-09-17 19:30 UTCEPSS rescoreEPSS 10% · 95th percentile
- 2026-09-16 14:08 UTCEPSS rescoreEPSS 10% · 95th percentile
- 2026-09-16 05:15 UTCEPSS rescoreEPSS 10% · 95th percentile
- 2026-09-15 03:11 UTCEPSS rescoreEPSS 10% · 95th percentile
- 2026-09-12 15:01 UTCEPSS rescoreEPSS 10% · 95th percentile
- 2026-09-11 14:53 UTCEPSS rescoreEPSS 10% · 95th percentile
- 2026-09-11 09:37 UTCEPSS rescoreEPSS 10% · 95th percentile
- 2026-09-10 09:34 UTCEPSS rescoreEPSS 10% · 95th percentile
- 2026-09-08 22:00 UTCEPSS rescoreEPSS 10% · 95th percentile
- 2026-09-07 16:01 UTCEPSS rescoreEPSS 10% · 95th percentile
- 2026-09-06 13:47 UTCEPSS rescoreEPSS 10% · 95th percentile
- 2026-09-04 05:06 UTCEPSS rescoreEPSS 10% · 95th percentile
- 2026-09-02 19:40 UTCOSV refresh
- 2026-09-02 14:11 UTCEPSS rescoreEPSS 10% · 95th percentile
- 2026-09-01 13:53 UTCEPSS rescoreEPSS 10% · 95th percentile
- 2026-09-01 04:39 UTCEPSS rescoreEPSS 10% · 95th percentile
- 2026-08-30 19:17 UTCEPSS rescoreEPSS 10% · 95th percentile
- 2026-08-30 01:22 UTCEPSS rescoreEPSS 10% · 95th percentile
- 2026-08-28 21:41 UTCEPSS rescoreEPSS 10% · 95th percentile
- 2026-08-27 14:25 UTCEPSS rescoreEPSS 10% · 95th percentile
- 2026-08-26 14:46 UTCEPSS rescoreEPSS 10% · 95th percentile
- 2026-08-25 13:49 UTCEPSS rescoreEPSS 10% · 95th percentile
- 2026-08-24 14:17 UTCEPSS rescoreEPSS 10% · 95th percentile
- 2026-08-23 00:19 UTCEPSS rescoreEPSS 10% · 95th percentile
- 2026-08-21 23:49 UTCEPSS rescoreEPSS 10% · 95th percentile
- 2026-08-20 22:55 UTCEPSS rescoreEPSS 10% · 95th percentile
- 2026-08-19 17:03 UTCEPSS rescoreEPSS 10% · 95th percentile
- 2026-08-18 13:48 UTCEPSS rescoreEPSS 10% · 95th percentile
- 2026-08-16 14:56 UTCEPSS rescoreEPSS 10% · 95th percentile
- 2026-08-16 07:54 UTCEG score recompute
- 2026-08-16 02:14 UTCEPSS rescoreEPSS 10% · 95th percentile
- 2026-08-15 02:12 UTCEG score recompute
- 2026-08-15 01:30 UTCEPSS rescoreEPSS 10% · 95th percentile
- 2026-08-14 05:22 UTCEG score recompute
- 2026-08-13 22:00 UTCEPSS rescoreEPSS 10% · 95th percentile
- 2026-08-12 19:37 UTCEG score recompute
- 2026-08-12 13:50 UTCEPSS rescoreEPSS 10% · 95th percentile
Publicly available exploits
(4 references)Public exploit code is referenced for this CVE (3 GitHub PoCs), as is 1 Nuclei detection template. A detection template checks whether a system is affected; it is not necessarily exploit code. Defenders should treat patch urgency accordingly.
- GitHub PoCinfernosalex/CVE-2026-33439-Python-PoCPublished Sep 12, 2026
Python PoC for CVE-2026-33439, an OpenAM pre-authentication RCE via jato.clientSession deserialization
Open source ↗ - GitHub PoCTheMalwareGuardian/CVE-2026-33439Published Apr 30, 2026
First publicly shared exploit implementation for CVE-2026-33439 (OpenAM pre-auth RCE via jato.clientSession deserialization).
Open source ↗ - GitHub PoCIbonok/CVE-2026-33439-PoCPublished Apr 28, 2026
CVE-2026-33439
Open source ↗ - Nucleihttp/cves/2026/CVE-2026-33439.yamlPublished Apr 17, 2026
OpenAM <= 16.0.5 - Pre-Auth RCE via jato.clientSession Deserialization
Open source ↗
Related CVEs(same CWE)
Frequently asked(5)
What is CVE-2026-33439?
When was the CVE record for CVE-2026-33439 published?
Is CVE-2026-33439 actively exploited?
What is the CVSS score of CVE-2026-33439?
How do I remediate CVE-2026-33439?
Dependency Blast Radius
See which npm, PyPI, Go, and Maven packages are affected by CVE-2026-33439
Is Your Infrastructure Affected by CVE-2026-33439?
EchelonGraph automatically scans your cloud infrastructure and maps CVE exposure using blast radius analysis.