# CVE-2026-71430: node-re2 process abort via large string replacement

Source: https://junglewise.ai/threats/cve-2026-71430-node-re2-process-abort-via-large-string-replacement  
Publisher: Junglewise Threat Intelligence, https://junglewise.ai/threats  
Published: 2026-08-06. Updated: 2026-08-06  
License: CC BY 4.0 with a link back

CVE-2026-71430 · Severity: medium · CVSS 6.2 · Published 2026-08-06

A vulnerability in the node-re2 library, a popular tool for safe regular expression processing in Node.js, can cause an entire application to crash. When an attacker provides a specific input that results in a very large replacement string, the library fails to handle the memory limit correctly, leading to an unrecoverable process failure. This results in a denial of service that cannot be caught or prevented by standard error-handling code.

Technologies: [re2 (npm)](https://junglewise.ai/threats/technologies/npm-re2), [Uhop Re2](https://junglewise.ai/threats/technologies/re2). Vendors: [npm](https://junglewise.ai/threats/vendors/npm), [Uhop](https://junglewise.ai/threats/vendors/uhop).

## Quick answers

**Is CVE-2026-71430 exploited in the wild?** No. Junglewise Threat Intelligence has no report of CVE-2026-71430 being exploited in the wild.

**How severe is CVE-2026-71430?** Medium severity, with a CVSS score of 6.2, published 6 August 2026.

**Which products and versions are affected?** re2 (npm) SEMVER:introduced=0,fixed=1.25.1; Uhop Re2 <= 1.25.0.

**Is there a fix for CVE-2026-71430?** Yes. re2 (npm): upgrade to 1.25.1 or later. Junglewise finds every place you run it, drafts the upgrade and applies it once you approve.

**How is CVE-2026-71430 attacked?** It is attacked with local access, in a software library.

**Am I affected by CVE-2026-71430?** Check whether you run re2 (npm) or Uhop Re2 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

- re2 (npm): upgrade to 1.25.1 or later

  ```sh
  npm install re2@1.25.1
  ```


## Technical details

The vulnerability exists in `WrappedRE2::Replace` within `lib/replace.cc`. When a global replacement using output-amplifying templates (like `$'` or `` $` ``) results in a string exceeding V8's `String::kMaxLength`, `Nan::New()` returns an empty `MaybeLocal`. The code calls `.ToLocalChecked()` on this empty handle without validation, triggering a fatal V8 error and a `SIGABRT`. Unlike the native Node.js regex engine which throws a catchable `RangeError`, this implementation causes a hard crash of the Node process. The issue is fixed in version 1.25.1 by adding proper checks for empty handles.

## Affected products

- uhop re2 <= 1.25.0

## Identifiers

- CVE-2026-71430
- GHSA-8hcv-x26h-mcgp

## Timeline

- 2026-07-07: disclosed
- 2026-08-06: advisory: GitHub Advisory published
- 2026-08-06: patched: Fixed in version 1.25.1

## References

- [https://api.github.com/users/ataberk-xyz](https://api.github.com/users/ataberk-xyz)
- [https://github.com/ataberk-xyz](https://github.com/ataberk-xyz)
- [https://api.github.com/users/ataberk-xyz/gists%7B/gist_id%7D](https://api.github.com/users/ataberk-xyz/gists%7B/gist_id%7D)
- [https://api.github.com/users/ataberk-xyz/repos](https://api.github.com/users/ataberk-xyz/repos)
- [https://avatars.githubusercontent.com/u/13886709?v=4](https://avatars.githubusercontent.com/u/13886709?v=4)
- [https://api.github.com/users/ataberk-xyz/events%7B/privacy%7D](https://api.github.com/users/ataberk-xyz/events%7B/privacy%7D)

## Related threats

- [uhop node-re2 out-of-bounds heap read in replace and split](https://junglewise.ai/threats/cve-2026-71498-uhop-node-re2-out-of-bounds-heap-read-in-replace-and-split)
- [uhop re2 infinite loop in String.prototype.match](https://junglewise.ai/threats/cve-2026-68499-uhop-re2-infinite-loop-in-string-prototype-match)
- [uhop node-re2 out-of-bounds read in exec and match functions](https://junglewise.ai/threats/cve-2026-67550-uhop-node-re2-out-of-bounds-read-in-exec-and-match-functions)