Quick answers
- Is CVE-2026-11539 exploited in the wild?
- No. Junglewise Threat Intelligence has no report of CVE-2026-11539 being exploited in the wild.
- How severe is CVE-2026-11539?
- Medium severity, with a CVSS score of 5.3, published 18 September 2026.
- Which products and versions are affected?
- IBM WebSphere Application Server 8.5 prior to 8.5.5.31, 9.0 prior to 9.0.5.29.
- Is there a fix for CVE-2026-11539?
- No fixed version is recorded yet. Check the vendor's advisory in the references below. If you run it, Junglewise drafts a mitigation that fits your setup and applies it once you approve, with senior security engineers behind it.
- How is CVE-2026-11539 attacked?
- It is attacked over the network.
- Am I affected by CVE-2026-11539?
- Check whether you run IBM WebSphere Application Server at an affected version. Junglewise does that check for you around the clock: connect your code, cloud and domains, and it matches new vulnerabilities like this one against what you actually run and tells you when one reaches you.
Technical details
The SOAP/JMX connector in IBM WebSphere Application Server 8.5 and 9.0 fails to properly validate authentication credentials, allowing unauthenticated remote attackers to bypass access controls via crafted SOAP requests. This enables unauthorized access to JMX management interfaces without requiring valid administrative credentials. The vulnerability is fixed in versions 8.5.5.31 and 9.0.5.29 and later.
Affected products
- IBM WebSphere Application Server 8.5 prior to 8.5.5.31, 9.0 prior to 9.0.5.29
Timeline
- 2026-09-18: disclosed