CVE-2026-71430 node-re2: String.prototype.replace(re2, template) aborts the Node process (uncatchable ToLocalChecked on empty MaybeLocal) when the result exceeds V8's max string length
An attacker can crash the Node.js process by triggering a regex replacement that exceeds V8's string length limit, causing an uncatchable abort.
- Exploited in the wild
- Not known
- Login needed
- Not needed
- Attackable
- Local or same network only
- Victim action needed
- Not needed
- Fix
- Available
What is CVE-2026-71430?
CVE-2026-71430 is a medium-severity denial of service vulnerability in uhop node-re2, published on 6 Aug 2026. It can only be exploited from the same machine or local network, with no action from the victim.
Official description
node-re2 provides RE2 regular expression bindings for Node.js. Prior to version 1.25.1, the WrappedRE2::Replace function built its replacement result and passed it to V8 using ToLocalChecked without checking for the empty MaybeLocal that V8 returns when the resulting string or buffer exceeds V8's maximum string length. When a global replace uses an output amplifying replacement template, the result can grow quadratically with the input size, and once the result exceeds V8's maximum string length, the unchecked ToLocalChecked call causes a fatal, uncatchable process abort instead of a catchable exception. This issue is fixed in version 1.25.1.
Weakness: CWE-617
Which versions are affected by CVE-2026-71430?
2 open source packages ship an affected version, including re2.
| Package | Affected | Fixed in |
|---|---|---|
re2 npm | All versions | 1.25.1 |
re2 npm | All versions | 1.25.1 |
How do I fix CVE-2026-71430?
Upgrade re2 to 1.25.1 or later.
Upgrade, then put limits on request size, rate and nesting depth so one client cannot exhaust the service. More about Denial of service.
Is CVE-2026-71430 being exploited?
It is not confirmed as exploited in the wild, but public exploit code for CVE-2026-71430 exists.
Sources
Also known as CLEANSTART-2026-ID87281, DEBIAN-CVE-2026-71430, GHSA-8hcv-x26h-mcgp, MINI-9fpv-fqh3-c3mq, UBUNTU-CVE-2026-71430.