Quick answers
- Is CVE-2026-110259 exploited in the wild?
- No. Junglewise Threat Intelligence has no report of CVE-2026-110259 being exploited in the wild.
- How severe is CVE-2026-110259?
- Medium severity, with a CVSS score of 5.5, published 14 October 2026.
- Which products and versions are affected?
- OW2 ASM 3.0 before 9.11.
- Is there a fix for CVE-2026-110259?
- Yes: fixed in ASM 9.11. Junglewise finds every place you run it, drafts the upgrade and applies it once you approve.
- How is CVE-2026-110259 attacked?
- It is attacked with local access, in a software library.
- Am I affected by CVE-2026-110259?
- Check whether you run OW2 ASM 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.
How to fix
- Fixed in: ASM 9.11
Technical details
The vulnerability is an uncontrolled recursion flaw in the ClassWriter.replaceAsmInstructions() method when processing forward jumps in large methods. An attacker can supply a specially crafted class file with many long forward jumps that trigger unbounded recursion in the toByteArray() method, resulting in a StackOverflowError. The flaw was fixed in version 9.11 with commit !459, which redesigned the bytecode storage mechanism to avoid recursion.
Affected products
- OW2 ASM 3.0 before 9.11
Timeline
- 2026-10-14: advisory