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.
References4
Metrics
- CVSS 3.1
-
5.7
MEDIUM
Score source: CNA
CVSS:3.1/AV:L/AC:H/PR:N/UI:N/S:U/C:L/I:N/A:H - EPSS — exploit probability
- 0% percentile: 5 · as of 13 November 2026
- CWE
- CWE-125
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