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Fencer Intel
medium 5.7

CVE-2026-67550 json

re2: Out-of-bounds heap read in `exec`/`test`/`match` via attacker-influenced `lastIndex` on a non-ASCII subject → uncatchable process crash (DoS)

published 4mo ago modified 19d ago also EUVD-2026-51297 , GHSA-ff84-5f28-78qj

cvss
5.7
version 3.1, CNA
cisa kev
Not listed
not in CISA's catalog
epss
0.2%
EPSS 0.2% chance of exploitation in 30 days, percentile 5%
public exploits
0
none known

Summary

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.

Patch / fix

  • npm re2 1.25.2
  • node-re2 Debian 14 1.26.1+~cs1.7.0-1

debian advisories DEBIAN-CVE-2026-67550

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Vendor advisories

What the vendors themselves say about their products: affected, fixed or not affected, and what to do.

red hat product security vex CVE-2026-67550 updated cvss 5.7

re2: Denial of Service via out-of-bounds read

  • Red Hat Enterprise Linux AI (RHEL AI) 3 re2
    affected: workaround, no fix available
  • Red Hat Hardened Images re2
    not affected: component not present

Red Hat CSAF VEX © Red Hat, Inc., from https://security.access.redhat.com/data/csaf/v2/vex/; changed: reduced to product statuses and remediations. CC BY 4.0 · csaf

CISA SSVC

Exploitation
Proof of concept is public
Automatable
no
Technical impact
partial
Assessed
3mo ago

Exploit prediction

0.16% chance of exploitation in the next 30 days, higher than 5% of all scored CVEs (FIRST EPSS, 2026-11-11).

Exploits and checks

  • github.com https://github.com/uhop/node-re2/security/advisories/GHSA-ff84-5f28-78qj referenced PoC, tagged "exploit" by a source, unverified

CVSS scores

assigned by version score vector
CNA 3.1 5.7 CVSS:3.1/AV:L/AC:H/PR:N/UI:N/S:U/C:L/I:N/A:H
GitHub 3.1 5.7 CVSS:3.1/AV:L/AC:H/PR:N/UI:N/S:U/C:L/I:N/A:H

Affected packages

ecosystem package affected fixed in
npm re2
<1.25.2
1.25.2

Affected products

  • uhop node-re2

Classification

Weakness

References

Sources

Fencer Intel keeps one entry per vulnerability: the CVE id wins, then GHSA, and records that alias each other are merged, except that two CVEs always keep separate entries. The same data is available as JSON.

The maintainers of uhop/node-re2 published their own advisory on GitHub. Reviewed sources take precedence over it.