Quick answers
- Is CVE-2026-118636 exploited in the wild?
- No. Junglewise Threat Intelligence has no report of CVE-2026-118636 being exploited in the wild.
- How severe is CVE-2026-118636?
- Critical severity, with a CVSS score of 9.8, published 31 October 2026.
- Which products and versions are affected?
- Apache Mina 3.0.0.
- Is there a fix for CVE-2026-118636?
- No fixed version is recorded yet. Upgrade to Apache MINA 2.2.X branch, as the 3.0.0 branch is inactive and no patch is planned for this issue. 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-2026-118636 attacked?
- It is attacked over the network, in a software library.
- Am I affected by CVE-2026-118636?
- Check whether you run Apache Mina 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
Upgrade to Apache MINA 2.2.X branch, as the 3.0.0 branch is inactive and no patch is planned for this issue.
Technical details
The JavaNativeMessageDecoder in Apache MINA 3.0's codec module calls ObjectInputStream.readObject() on frame bytes without implementing a class filter, enabling gadget-chain remote code execution. An attacker can exploit this by sending specially crafted serialized Java objects to an application using this decoder with untrusted network peers. The vulnerability requires network access but no authentication, and the MINA 3.0 branch is no longer maintained; users are advised to migrate to MINA 2.2.X.
Affected products
- Apache MINA 3.0.0
Timeline
- 2026-10-31: disclosed