CVE-2026-110095 fast-uri CVE debrief

Who should care

Node.js developers and administrators using fast-uri in their applications should assess exposure and upgrade to fixed versions. They should verify affected systems and apply workarounds if necessary. The vulnerability can lead to security issues in Node.js applications, including potential unauthorized access to resources and possible security bypass.

Why it matters

The fast-uri vulnerability can lead to security issues in Node.js applications. Developers and administrators should assess exposure, upgrade to fixed versions, and verify affected systems.

• Potential unauthorized access to resources
• Possible security bypass in Node.js applications
• Verification of affected systems and versions required
• Upgrade to fixed versions to prevent exploitation

Technical summary

The fast-uri library is vulnerable to improper path equivalence in relative reference normalization. An attacker-supplied or user-supplied relative reference can escape its intended directory and point at a different resource. The vulnerability can lead to security issues in Node.js applications, including potential unauthorized access to resources and possible security bypass. The issue is fixed in fast-uri 2.4.8, 3.1.9, and 4.2.3. 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.

Defensive priority

Upgrade to fixed versions and verify affected systems

Recommended defensive actions

• Upgrade to fast-uri version 2.4.8, 3.1.9, or 4.2.3
• Verify affected systems and apply workarounds if necessary
• Monitor for potential security issues in Node.js applications using fast-uri
• Confirm whether affected product deployments exist in managed environments and assign an owner for follow-up
• Review the supplied official advisory or CVE record to validate affected scope, severity, and vendor guidance
• Plan vendor-supported updates or mitigations through normal change control where exposure is confirmed
• Check relevant monitoring, detection, and logs for exposed assets that need extra review

Evidence notes

The CVE record and source item provide details on the vulnerability in fast-uri. The issue is fixed in fast-uri 2.4.8, 3.1.9, and 4.2.3. The vulnerability can lead to security issues in Node.js applications. Developers and administrators should assess exposure, upgrade to fixed versions, and verify affected systems. The fast-uri library is vulnerable to improper path equivalence in relative reference normalization. An application that normalizes an attacker-supplied or user-supplied relative reference and then resolves it, or uses it

Sources and references

Methodology and review provenance

AI-assisted synthesis based on stored public vulnerability evidence. System validation, approval state, and publication status do not by themselves establish human review of this revision. PatchSiren helps prioritize defensive review and does not prove exposure or remediation on any system.