npm package `expr-eval` is vulnerable to Prototype Pollution. An attacker with access to express eval interface can use JavaScript prototype-based inheritance model to achieve arbitrary code execution. The npm expr-eval-fork package resolves this issue.
CVE-2025-13204
CVSS base score
9.8 (v3.1)
Severity
CRITICAL
Attack vector
Network
Weakness
CWE-1321
Last modified
October 30, 2026
CVSS vector
CVSS:3.1/AV:N/AC:L/PR:N/UI:N/S:U/C:H/I:H/A:H
Affected products
silentmatt javascript expression evaluator
References
- github.com Product
- github.com Product
- github.com Product
- github.com Issue Tracking, Patch
- github.com Product
- www.huntr.dev Exploit, Third Party Advisory
- www.npmjs.com Product