CVE-2026-110095: fast-uri vulnerable to improper path equivalence in relative reference normalization

CVE-2026-110095 · Severity: low · CVSS 3.7 · Published 2026-10-20

fast-uri is a dependency-free RFC 3986 URI parser and serializer for Node.js. In versions before 2.4.8, from 3.0.0 through 3.1.8, and from 4.0.0 through 4.2.2, the normalize() and serialize() functions apply RFC 3986 dot-segment removal to the path of a relative-path reference, even though that algorithm is defined only for the merged target path during resolution, so a leading parent-directory segment can be dropped and a document-relative reference can become root-relative. An application that normalizes an attacker-supplied or user-supplied relative reference and then resolves it, or uses it as a cache, deduplication, or authorization key, can have the reference escape its intended directory and point at a different resource. The issue is fixed in fast-uri 2.4.8, 3.1.9, and 4.2.3, and users should upgrade to one of these versions or later. As a workaround, resolve a relative reference against its absolute base first and normalize the absolute result instead of normalizing the reference beforehand.

Technologies: fast-uri (npm). Vendors: npm.

Quick answers

Is CVE-2026-110095 exploited in the wild?
No. Junglewise Threat Intelligence has no report of CVE-2026-110095 being exploited in the wild.
How severe is CVE-2026-110095?
Low severity, with a CVSS score of 3.7, published 20 October 2026.
Which products and versions are affected?
fast-uri (npm) < 2.4.8, SEMVER:introduced=0,fixed=2.4.8.
Is there a fix for CVE-2026-110095?
Yes. fast-uri (npm): upgrade to 2.4.8 or later. Junglewise finds every place you run it, drafts the upgrade and applies it once you approve.
Am I affected by CVE-2026-110095?
Check whether you run fast-uri (npm) at an affected version. Junglewise does that check for you around the clock: connect your code, cloud and domains, and it matches new vulnerabilities like this one against what you actually run and tells you when one reaches you.

How to fix

  • fast-uri (npm): upgrade to 2.4.8 or later
    npm install fast-uri@2.4.8

Affected products

  • fast-uri (npm) < 2.4.8, SEMVER:introduced=0,fixed=2.4.8

Identifiers

  • CVE-2026-110095
  • GHSA-xhq7-xmqj-769h

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