CVE-2025-13204: silentmatt expr-eval Prototype Pollution

Vulnerability summary

CVE-2025-13204 is a high (CVSS 7.3) Prototype Pollution vulnerability in silentmatt expr-eval. EPSS estimates a 0.48% chance of exploitation in the next 30 days, higher than 40.4% of scored vulnerabilities. 2 public exploits are recorded.

Timeline

1. 14-11-2025
   PublishedVulnerability first disclosed.
2. 14-11-2025
   Last modifiedVulnerability information updated.

Description

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.

• CWE-1321Improperly Controlled Modification of Object Prototype Attributes ('Prototype Pollution')The product receives input from an upstream component that specifies attributes that are to be initialized or updated in an object, but it does not properly control modifications of attributes of the object prototype.