CVE-2026-9330: IBM WebSphere Application Server · Deserialization of Untrusted Data
Affects IBM WebSphere Application ServerSource CVE Database V5
Not known to be exploited · CVSS 8.5 High.
Data as of 30 Oct 2026, 11:52 UTC
- EPSS
- 0.5% chance of exploitation in 30 days – higher than 43% of CVEsExploit Prediction Scoring System: the likelihood attackers will use this flaw soon.
CVSS:3.1/AV:N/AC:H/PR:L/UI:N/S:C/C:H/I:H/A:HExploitation evidence
Disclosed: evidence found.
CVE published 1 Jun 2026
Detectable: no evidence on record.
No public nuclei template indexed
Weaponized: no evidence on record.
No public exploit code indexed in Metasploit or Exploit-DB
Exploited in the wildExploited: no evidence on record.
Not in CISA KEV and no source reports exploitation
Observed by OffSeq MirageSeen by Mirage: no evidence on record.
No attack traffic recorded by OffSeq Mirage sensors
A missing step is not evidence of safety. Sources: cve.org (opens in a new tab), the Metasploit, Exploit-DB and nuclei-templates index as of 30 Oct 2026.
What to do
Affected software
| Product | Affected | Fixed in |
|---|---|---|
| IBMWebSphere Application Server | Affected
| Fixed in– |
CPE configurations (4)
cpe:2.3:a:ibm:websphere_application_server:9.0:*:*:*:*:*:*:*cpe:2.3:a:ibm:websphere_application_server:9.0.0:*:*:*:*:*:*:*cpe:2.3:a:ibm:websphere_application_server:8.5:*:*:*:*:*:*:*cpe:2.3:a:ibm:websphere_application_server:8.5.0:*:*:*:*:*:*:*
AI-suggested
Users should monitor IBM's security advisories for updates and apply patches promptly once available. Until a fix is released, consider restricting access to the SAML Web Single Sign-On component to trusted networks and implement compensating controls such as web application firewalls to detect and block suspicious deserialization payloads.
Description
IBM WebSphere Application Server versions 8.5 and 9.0 contain a vulnerability in the SAML Web Single Sign-On component where improper validation of user-supplied data during deserialization can lead to remote code execution. This occurs when a crafted HTTP request is combined with a suitable gadget chain. The vulnerability is tracked as CVE-2026-9330 and has a high severity score of 8.5. No official patch or remediation guidance has been provided yet by IBM. There are no known exploits in the wild at this time.