CVE-2025-36038: IBM WebSphere Application Server · Deserialization of Untrusted Data
Affects IBM WebSphere Application ServerSource CVE Database V5
Not known to be exploited · 13% EPSS · CVSS 9.0 Critical.
Data as of 26 Oct 2026, 14:05 UTC
- EPSS
- 13.3% chance of exploitation in 30 days – higher than 96% of CVEsExploit Prediction Scoring System: the likelihood attackers will use this flaw soon.
CVSS:3.1/AV:N/AC:H/PR:N/UI:N/S:C/C:H/I:H/A:HExploitation evidence
Disclosed: evidence found.
CVE published 25 Jun 2025
Detectable: no evidence on record.
No public nuclei template indexed
Weaponised: 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 26 Oct 2026.
What to do
Affected software
| Product | Affected | Fixed in |
|---|---|---|
Mavencom.ibm.websphere/websphere-application-serverpkg:maven/com.ibm.websphere/websphere-application-serverOther threats | Affected
| Fixed in– |
Check your own hosts for these packages with threat-finder (opens in a new tab), our free open-source scanner.
AI-suggested
- Apply official patches from IBM as soon as they are released to address CVE-2025-36038. Monitor IBM security advisories closely for updates.
- Until patches are available, restrict network access to WebSphere Application Server management and administrative interfaces using firewalls, VPNs, or network segmentation to limit exposure to untrusted networks.
- Implement strict input validation and deserialization controls where possible, including disabling or restricting deserialization of untrusted data in application code and middleware configurations.
- Employ Web Application Firewalls (WAFs) with custom rules to detect and block suspicious serialized object payloads targeting WebSphere endpoints.
- Monitor logs and network traffic for anomalous activity indicative of exploitation attempts, such as unusual serialized object sequences or unexpected remote code execution indicators.
- Conduct regular security assessments and penetration testing focusing on deserialization vulnerabilities and middleware security.
- Educate development and operations teams about secure deserialization practices and the risks associated with untrusted data processing.
- Consider deploying runtime application self-protection (RASP) solutions to detect and prevent exploitation attempts in real time.
- Maintain an incident response plan tailored to middleware compromise scenarios to enable rapid containment and recovery.
Description
IBM WebSphere Application Server 8.5 and 9.0 could allow a remote attacker to execute arbitrary code on the system with a specially crafted sequence of serialized objects.