Vulnerability · Published Jul 30, 2026 · Assigned by GitHub_M
CVE-2026-67550re2: Out-of-bounds heap read in `exec`/`test`/`match` via attacker-influenced `lastIndex` on a non-ASCII subject → uncatchable process crash (DoS)
Medium 5.7
In plain English
A medium-severity out-of-bounds read in node-re2 from uhop. Proof-of-concept exploit code is public. The chance it is exploited in the next 30 days is estimated at 0.2% (higher than 5% of all known vulnerabilities). Fixed versions are available - upgrade the affected package.
Official description
re2 provides Node.js bindings for Google's RE2 regular expression engine. Prior to 1.25.2, re2 validates lastIndex against the UTF-8 byte length of a subject but uses it as a UTF-16 code-unit offset in exec, test, match, replace, and split, allowing an attacker-influenced lastIndex on a non-ASCII subject to trigger an out-of-bounds heap read and an uncatchable process crash, with limited heap information disclosure in some cases. This issue is fixed in 1.25.2.
Affected packages & fixed versions
| Ecosystem | Package | Fixed in | Advisory |
|---|---|---|---|
| Debian:12 | node-re2 | no fix listed | DEBIAN-CVE-2026-67550 |
| Debian:13 | node-re2 | no fix listed | DEBIAN-CVE-2026-67550 |
| Debian:14 | node-re2 | 1.26.1+~cs1.7.0-1 | DEBIAN-CVE-2026-67550 |
| Ubuntu:22.04:LTS | node-re2 | no fix listed | UBUNTU-CVE-2026-67550 |
| Ubuntu:24.04:LTS | node-re2 | no fix listed | UBUNTU-CVE-2026-67550 |
| Ubuntu:26.04:LTS | node-re2 | no fix listed | UBUNTU-CVE-2026-67550 |
| Ubuntu:26.10 | node-re2 | no fix listed | UBUNTU-CVE-2026-67550 |
| npm | re2 | 1.25.2 | GHSA-ff84-5f28-78qj |
Affected products (as reported)
Weakness: CWE-125 · Vector: CVSS:3.1/AV:L/AC:H/PR:N/UI:N/S:U/C:L/I:N/A:H
References
- https://github.com/uhop/node-re2/security/advisories/GHSA-ff84-5f28-78qj x_refsource_CONFIRM
- https://github.com/uhop/node-re2/commit/56293de4fc0914d7bc35f92e98de25b0d9bb417d x_refsource_MISC
- https://github.com/uhop/node-re2/releases/tag/1.25.2 x_refsource_MISC