CVE-2026-44267 Elo: Sandbox escape to arbitrary Node.js / browser code execution via unfiltered `.constructor` member access in Elo JavaScript emitter
- Published
- Updated
- Exploit status
- No public exploit known
Description
Elo is a purely functional expression language for no-code tools. Prior to 1.0.1, plain Elo strings supplied to defaultFormats.elo.parse(), bin/elo, or elo-lang.org/try can use .constructor.constructor to reach JavaScript Function because the member_access handler in src/transform.ts does not reject meta-properties, src/compilers/javascript.ts emits the surviving property directly, and src/parser.ts accepts constructor as an ordinary identifier. The resulting generated JavaScript executes attacker-selected code in the host runtime. This permits browser script execution and session compromise on the auto-running playground and arbitrary Node.js code execution on library, CI, or DevOps hosts. This plain-string path is distinct from the programmatic AST-object injection issue. This issue is fixed in version 1.0.1.
Affected products
| Product | Affected versions | Fixed in |
|---|---|---|
| enspirit elo | = < 1.0.1 | No fix listed |
| enspirit elo(npm) | <= 1.0.0 | No fix listed |