# CVE-2026-126367: @grpc/grpc-js: safe_regex incorrectly applies partial string matching for patterns with alternation

Status: published. Published: 2026-11-12. Updated: 2026-11-12.

@grpc/grpc-js implements the core functionality of gRPC purely in JavaScript, without a C++ addon. Before 1.13.2, and from 1.14.0 through 1.14.1, the @grpc/grpc-js-xds SafeRegexValueMatcher and PathSafeRegexValueMatcher add start and end anchors without grouping a supplied top-level alternation. An expression intended to match one of several complete values can therefore match a prefix, substring, or suffix. The affected matchers are used for route selection, xDS credential identity matching, and RBAC URL path, principal name, server name, and header rules. An ALLOW policy using an alternation can consequently accept a method, certificate identity, or header value outside the intended set, while a DENY policy becomes broader rather than permissive. This issue is fixed in versions 1.13.2 and 1.14.2.

## Remediation

No remediation reported in collected sources

## Affected products and versions

- grpc / grpc-node: < 1.13.2 (affected); >= 1.14.0, < 1.14.2 (affected). Source: CNA: GitHub_M

## Severity and prioritization

- CVSS 3.1: 4.8 (medium); CVSS:3.1/AV:N/AC:H/PR:N/UI:N/S:U/C:L/I:L/A:N; source: CNA: GitHub_M

- CISA KEV: No listing in collected sources

- EPSS: Not available

- SSVC: Not available

- Weaknesses: CWE-625, CWE-863

## Exploit evidence

No exploit evidence in collected sources. This is not proof of no exploitation.

## References

- https://github.com/grpc/grpc-node/security/advisories/GHSA-r7hq-q2xm-6c5m (CNA: GitHub_M; x_refsource_CONFIRM)

- https://github.com/grpc/grpc-node/commit/3fc3b0ebf7a89d64843a73679951142d33b40cb1 (CNA: GitHub_M; x_refsource_MISC)

- https://github.com/grpc/grpc-node/commit/57a67e96babcb29b6eabc1833221ccf2fa152d43 (CNA: GitHub_M; x_refsource_MISC)

- https://github.com/grpc/grpc-node/releases/tag/@grpc/grpc-js-xds@1.13.2 (CNA: GitHub_M; x_refsource_MISC)

- https://github.com/grpc/grpc-node/releases/tag/@grpc/grpc-js-xds@1.14.2 (CNA: GitHub_M; x_refsource_MISC)

## Provenance

- CNA: GitHub_M: https://www.cve.org/CVERecord?id=CVE-2026-126367; retrieved 2026-11-12; source updated 2026-11-12

Revision: 1f7a8f095375b8e0d5e8c7341bc43b970a6e1c51f6b504ce6169f1823a0c28db

Canonical: https://y2.dev/cve/CVE-2026-126367

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