Quick answers
- Is CVE-2026-119137 exploited in the wild?
- No. Junglewise Threat Intelligence has no report of CVE-2026-119137 being exploited in the wild.
- How severe is CVE-2026-119137?
- Medium severity, with a CVSS score of 5.3, published 29 October 2026.
- Which products and versions are affected?
- Bytecode Alliance Wasmtime 42.0.0 to before 48.0.6; 49.0.0 to before 49.0.3.
- Is there a fix for CVE-2026-119137?
- Yes: fixed in 48.0.6, 49.0.3. Junglewise finds every place you run it, drafts the upgrade and applies it once you approve.
- How is CVE-2026-119137 attacked?
- It is attacked over the network, in a software library.
- Am I affected by CVE-2026-119137?
- Check whether you run Bytecode Alliance Wasmtime 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: 48.0.6, 49.0.3
Technical details
The vulnerability is uncontrolled recursion (CWE-674) in Wasmtime's type registry cleanup logic. When a guest drops a top-level type, the host iteratively drops inner types; a long chain of recursive types can cause unbounded recursive calls that exhaust the stack. The issue was reintroduced in version 42.0.0 when recursion was accidentally added back to code that had previously been converted to an iterative loop. Any WebAssembly guest can trigger this remotely via network.
Affected products
- Bytecode Alliance Wasmtime 42.0.0 to before 48.0.6; 49.0.0 to before 49.0.3
Timeline
- 2026-10-14: disclosed
- 2026-10-29: advisory