CVE-2026-9330 | IBM WebSphere Application Server is affected by remote code execution

IBM WebSphere Application Server 9.0, and 8.5 is affected by an improper validation of user-supplied data during deserialization using the SAML Web Single Sign-On component. This could result in remote code execution via a crafted HTTP request when combined with a suitable gadget chain.

Published: 2026-06-01 Last update: 2026-06-04 Assigner: [email protected] Source: [email protected]

Conclusion & alert: CVE-2026-9330 is rated Moderate Risk (51.9/100): CVSS High severity, with medium exploitation likelihood (EPSS 0.28%). Mandatory action: Review affected assets and schedule remediation.

Risk is dynamic; we continuously reassess and refresh what is shown on this page as upstream context changes.

Exploit prediction scoring system (EPSS) score for CVE-2026-9330

EPSS lead: Daily EPSS estimates relative likelihood of exploitation; percentile ranks this CVE among scored vulnerabilities (higher = more severe relative rank).

# Date Old EPSS score New EPSS score Delta (New - Old)
1 2026-06-05 0.36% 0.28% -0.08%
2 2026-06-02 0.36%

Full EPSS history (2 records total)

Common vulnerability scoring system (CVSS) metrics for CVE-2026-9330

CVSS metrics for this CVE.

Base score Version Severity Vector Exploitability Impact Score source
8.5 3.1 HIGH
CVSS:3.1/AV:N/AC:H/PR:L/UI:N/S:C/C:H/I:H/A:H Click to expand
Attack vector (AV:N)
Could be attacked over the internet or any normal routed network—not just someone sitting at the machine.
Attack complexity (AC:H)
Even with access, the exploit needs extra luck, timing, or a fussy environment to actually work.
Privileges required (PR:L)
A normal user session is enough; they don’t have to be admin.
User interaction (UI:N)
Nobody has to click “OK” or open a trap file; it can work without a victim helping.
Scope (S:C)
Breaking this can reach past the original component and bite other resources—bigger blast radius.
Confidentiality (C:H)
Serious risk that confidential data gets exposed in a big way.
Integrity (I:H)
They could widely tamper with or forge data—trust in the data is badly hurt.
Availability (A:H)
Could take the service down hard or make it unusable for people who depend on it.
1.8 6.0 [email protected]

Weakness enumeration for CVE-2026-9330

GitHub Security Advisory for CVE-2026-9330

GHSA-xrfh-q76x-p6f2 · Severity: high — IBM WebSphere Application Server 9.0, and 8.5 is affected by an improper validation of user...

Affected software / configurations for CVE-2026-9330

Vendor Product Version Raw CPE
ibm websphere_application_server >= 8.5.0.0, < 8.5.5.30 cpe:2.3:a:ibm:websphere_application_server:*:*:*:*:traditional:*:*:*
ibm websphere_application_server >= 9.0.0.0, < 9.0.5.29 cpe:2.3:a:ibm:websphere_application_server:*:*:*:*:traditional:*:*:*

References for CVE-2026-9330

cvelogic Threat Intelligence