CVE-2026-55107
Kobako is a Ruby gem that embeds a Wasm-isolated mruby interpreter inside applications, allowing…
- Risk score
- 76/100
- CVSS
- 10.0 v3.1
- Exploit chance (30 days)
- 0.8%
- Published
- 30 Sep 2026
Open in the live forecast Today's forecast
What to know
- What it is
- Kobako is a Ruby gem that embeds a Wasm-isolated mruby interpreter inside applications, allowing execution of untrusted Ruby scripts (LLM-generated code, user formulas, student submissions, third-party plugins) in-process without giving them access to host memory, files, network, or credentials. From version 0.1.0 to …
- Affected
- See advisory
- Fix
- Upgrade the product to 0.9.1 or later.
- Exploitation
- No known exploitation
Why it is Amber
- CVSS 10.0 critical
- Remotely exploitable without logging in
References
Original description
Kobako is a Ruby gem that embeds a Wasm-isolated mruby interpreter inside applications, allowing execution of untrusted Ruby scripts (LLM-generated code, user formulas, student submissions, third-party plugins) in-process without giving them access to host memory, files, network, or credentials. From version 0.1.0 to before version 0.9.1, a guest mruby script running inside the Kobako sandbox can execute arbitrary Ruby in the host process, fully escaping the sandbox. This issue has been patched in version 0.9.1.
Last activity 30 Sep 2026. Patch Forecast updates every hour.