Quick answers
- Is CVE-2026-89059 exploited in the wild?
- No. Junglewise Threat Intelligence has no report of CVE-2026-89059 being exploited in the wild.
- How severe is CVE-2026-89059?
- High severity, with a CVSS score of 7.5, published 18 September 2026.
- Which products and versions are affected?
- Red Hat RESTEasy unknown.
- Is there a fix for CVE-2026-89059?
- 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-2026-89059 attacked?
- It is attacked over the network.
- Am I affected by CVE-2026-89059?
- Check whether you run Red Hat RESTEasy 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 vulnerability is a denial of service flaw in RESTEasy's IIOImageProvider component, which processes image data from HTTP request bodies. The root cause is insufficient validation of image dimensions and pixel counts declared in attacker-supplied image payloads. A remote, unauthenticated attacker can craft a small image file with falsely declared enormous dimensions to trigger excessive heap allocation, exhausting JVM memory and causing a denial of service. The attack requires only network reachability to an exposed RESTEasy image endpoint; no authentication is needed. Patches should be available from the vendor.
Affected products
- Red Hat RESTEasy unknown
Timeline
- 2026-09-18: disclosed: CVE-2026-89059 published