CVE-2026-17495: moment vulnerable to Path Traversal via crafted non-string locale name

Severity: medium (CVSS 5.9 v3.1)
Exploited in the wild: not listed in CISA KEV
EPSS: 0.5% probability of exploitation in the next 30 days
Public exploit or detection template: none known
Published: 2026-09-15 · updated 2026-09-16
Weakness: CWE-27

Description

moment is a JavaScript date library for parsing, validating, manipulating, and formatting dates. In versions 2.29.2 through 2.30.1, a specially crafted non-string object passed to moment.locale() can bypass the locale-name path-traversal guard. The guard assumes the input is a string, so an object whose match() method satisfies the check while its toString() returns a traversal path reaches an internal require() call with attacker-controlled path segments. This is an incomplete fix for CVE-2022-24785 and primarily affects npm (server-side) users that pass user-provided input directly to moment.locale(). The issue is fixed in moment 2.31.0, and users should upgrade to 2.31.0 or later. As a workaround, validate that any user-supplied input is a string before passing it to moment.locale().

Affected products

moment: from 2.29.2 before 2.31.0 — fixed in 2.31.0

How to fix

Upgrade to a fixed version: moment 2.31.0. Check the vendor advisory for mitigations.

References

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