Quick answers
- Is CVE-2025-13204 exploited in the wild?
- No. Junglewise Threat Intelligence has no report of CVE-2025-13204 being exploited in the wild.
- How severe is CVE-2025-13204?
- High severity, with a CVSS score of 7.3, published 14 November 2025.
- Which products and versions are affected?
- expr-eval-fork (npm) SEMVER:introduced=0,fixed=2.0.2.
- Is there a fix for CVE-2025-13204?
- Yes. expr-eval-fork (npm): upgrade to 2.0.2 or later. Junglewise finds every place you run it, drafts the upgrade and applies it once you approve.
- How is CVE-2025-13204 attacked?
- It is attacked over the network, in a software library.
- Am I affected by CVE-2025-13204?
- Check whether you run expr-eval-fork (npm) or Silentmatt Javascript Expression Evaluator at an affected version. Junglewise does that check for you around the clock: connect your code, cloud and domains, and it matches new vulnerabilities like this one against what you actually run and tells you when one reaches you.
How to fix
- expr-eval-fork (npm): upgrade to 2.0.2 or later
npm install expr-eval-fork@2.0.2
Technical details
expr-eval is vulnerable to prototype pollution (CWE-1321), a vulnerability in JavaScript's prototype-based inheritance model. An attacker with access to the expression evaluation interface can inject specially crafted payloads that manipulate the __proto__, prototype, or constructor properties to pollute the global object prototype. This enables arbitrary code execution in the context of the application. The vulnerability affects all versions of expr-eval up to and including 2.0.2, and is fixed in expr-eval-fork 2.0.2. The attack requires network access to the eval interface but no authentication, and the fix involves adding explicit checks to reject variable names matching /^__proto__|prototype|constructor$/.
Affected products
- expr-eval up to 2.0.2
Identifiers
- CVE-2025-13204
- GHSA-8gw3-rxh4-v6jx
Timeline
- 2025-11-14: disclosed
- 2025-11-17: patched: Fixed in expr-eval-fork 2.0.2