Is CVE-2025-12735 exploited in the wild?

No. Junglewise Threat Intelligence has no report of CVE-2025-12735 being exploited in the wild.

How severe is CVE-2025-12735?

Critical severity, with a CVSS score of 9.8, published 5 November 2025.

Which products and versions are affected?

expr-eval-fork (npm) SEMVER:introduced=0,fixed=3.0.1.

Is there a fix for CVE-2025-12735?

Yes. expr-eval-fork (npm): upgrade to 3.0.1 or later. Junglewise finds every place you run it, drafts the upgrade and applies it once you approve.

How is CVE-2025-12735 attacked?

It is attacked with local access or over the network, in a software library.

Am I affected by CVE-2025-12735?

Check whether you run Jorenbroekema Javascript Expression Evaluator, 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.

CVE-2025-12735: expr-eval arbitrary code execution via unvalidated function argument

CVE-2025-12735 · Severity: critical · CVSS 9.8 · Published 2025-11-05

expr-eval is a JavaScript library used to safely evaluate mathematical expressions. An attacker can bypass input validation by passing a crafted variables object to the evaluate() function, leading to arbitrary code execution on the server or client where the library is used.

Vendors: npm, Silentmatt.

Quick answers

Is CVE-2025-12735 exploited in the wild?: No. Junglewise Threat Intelligence has no report of CVE-2025-12735 being exploited in the wild.
How severe is CVE-2025-12735?: Critical severity, with a CVSS score of 9.8, published 5 November 2025.
Which products and versions are affected?: expr-eval-fork (npm) SEMVER:introduced=0,fixed=3.0.1.
Is there a fix for CVE-2025-12735?: Yes. expr-eval-fork (npm): upgrade to 3.0.1 or later. Junglewise finds every place you run it, drafts the upgrade and applies it once you approve.
How is CVE-2025-12735 attacked?: It is attacked with local access or over the network, in a software library.
Am I affected by CVE-2025-12735?: Check whether you run Jorenbroekema Javascript Expression Evaluator, 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 3.0.1 or later
```
npm install expr-eval-fork@3.0.1
```

Technical details

The vulnerability is a code injection flaw (CWE-94) in the expr-eval library's evaluate() function. The library fails to properly validate and restrict functions passed through the variables parameter, allowing an attacker to inject and execute arbitrary code. The attack vector is local or network-dependent on how the application uses the library—if the evaluate() function is called with user-controlled input without additional validation, an attacker can craft a malicious variables object to achieve remote code execution. Patches have been proposed in pull requests #288 and #289 on the upstream repository, and a fix is available in expr-eval-fork version 3.0.1 and later.

Affected products

expr-eval expr-eval 0 through 2.0.2
expr-eval expr-eval-fork 0 through 3.0.0

Identifiers

CVE-2025-12735
GHSA-jc85-fpwf-qm7x

Timeline

2025-11-05: disclosed: Published as GHSA-jc85-fpwf-qm7x
2025-11-05: advisory: CVE-2025-12735 assigned

References

https://github.com/silentmatt/expr-eval/pull/288

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