Description
The expr-eval library is a JavaScript expression parser and evaluator designed to safely evaluate mathematical expressions with user-defined variables. However, due to insufficient input validation, an attacker can pass a crafted context object or use MEMBER of the context object into the evaluate() function and trigger arbitrary code execution.
Affected products
jorenbroekema: javascript expression evaluator; silentmatt: javascript expression evaluator
References9
- github.com/silentmatt/expr-eval/pull/288 Issue TrackingPatch
- github.com/advisories/GHSA-jc85-fpwf-qm7x Third Party Advisory
- github.com/jorenbroekema/expr-eval Product
- github.com/silentmatt/expr-eval Product
- kb.cert.org/vuls/id/263614 Third Party Advisory
- www.npmjs.com/package/expr-eval Product
- www.npmjs.com/package/expr-eval-fork Product
- www.kb.cert.org/vuls/id/263614 Third Party Advisory
- github.com/jorenbroekema/expr-eval/blob/460b820ba01c5aca6c5d84a… Product
Metrics
- CVSS 3.1
-
9.8
CRITICAL
Score source: CNA
CVSS:3.1/AV:N/AC:L/PR:N/UI:N/S:U/C:H/I:H/A:H - EPSS — exploit probability
- 2% percentile: 78 · as of 10 November 2026
- CWE
- CWE-94
Could this be exploited in your environment?
A patch closes the known hole. A penetration test shows what an attacker can still reach — with proof.