CVE-2025-55173

A vulnerability in Next.js Image Optimization allowed attacker-controlled image servers to trigger arbitrary file downloads with custom content and filenames. Exploitation required permissive images.domains or images.remotePatterns and user interaction.

Binary-Affected: Next.js Upstream-version-introduced: v14.2.30 Upstream-version-fixed: v15.4.5 and v14.2.31

This issue is classified as Moderate rather than Important because exploitation requires a very specific set of conditions: the target Next.js app must be configured with permissive external image domains or patterns, the attacker must control or influence the remote image server, and a user must be tricked into clicking a crafted link. The vulnerability does not provide direct code execution, privilege escalation, or server compromise—it primarily enables arbitrary file downloads, which increases the risk of phishing and social engineering rather than direct technical exploitation. Since the attack vector relies on user interaction and misconfiguration rather than a default behavior, the overall impact is contained, making it less severe than flaws that directly compromise application integrity or confidentiality.

The CVSS score(s) listed for this vulnerability do not reflect the associated product's status, and are included for informational purposes to better understand the severity of this vulnerability.

Mitigation includes restricting images.domains and images.remotePatterns to trusted hosts only, avoiding permissive configurations, and monitoring logs for suspicious image fetches.