WAF - WAF Release - 2026-08-26 - Emergency

<p>This emergency release updates an existing Next.js remote code execution rule to identify CVE-2026-75604 and adds a new rule for remote code execution in the Next.js Image Optimizer via crafted AVIF images.</p> <p><strong>Key Findings</strong></p> <ul> <li> <p>CVE-2026-75604 affects Windows-hosted Next.js applications using both the Pages Router and App Router without Cache Components and can lead to unauthenticated remote code execution.</p> </li> <li> <p>GHSA-2xp9-vwfh-vxw4 affects the Next.js Image Optimizer and can lead to unauthenticated remote code execution when it optimizes an attacker-controlled AVIF image.</p> </li> </ul> <p><strong>Impact</strong></p> <p>Next.js recommends updating to version 16.3.3 or 15.5.24 to address these vulnerabilities.</p> <table style="width: 100%"><thead><tr><th>Ruleset</th><th>Rule ID</th><th>Legacy Rule ID</th><th>Description</th><th>Previous Action</th><th>New Action</th><th>Comments</th></tr></thead><tbody><tr><td>Cloudflare Managed Ruleset</td><td><span class="rule-id" data-rule-id="2b6b94ec864d47f99630ecf72ca6cce3"><button type="button" title="Copy rule ID" aria-label="Copy rule ID 2b6b94ec864d47f99630ecf72ca6cce3" class="border-border bg-muted hover:border-foreground/30 hover:bg-accent inline-flex cursor-copy items-center rounded-md border px-1.5 py-0.5 transition-colors duration-150"><span class="font-mono text-[0.8125rem] font-medium">...2ca6cce3</span></button></span></td><td>N/A</td><td>Next.js - Remote Code Execution - CVE:CVE-2026-75604</td><td>Block</td><td>N/A</td><td>Rule metadata description refined. Detection unchanged.</td></tr><tr><td>Cloudflare Managed Ruleset</td><td><span class="rule-id" data-rule-id="18b22b0bd423423c945b3a0180256efe"><button type="button" title="Copy rule ID" aria-label="Copy rule ID 18b22b0bd423423c945b3a0180256efe" class="border-border bg-muted hover:border-foreground/30 hover:bg-accent inline-flex cursor-copy items-center rounded-md border px-1.5 py-0.5 transition-colors duration-150"><span class="font-mono text-[0.8125rem] font-medium">...80256efe</span></button></span></td><td>N/A</td><td>Next.js - Image Optimizer Remote Code Execution via Crafted AVIF</td><td>N/A</td><td>Block</td><td>This is a new detection.</td></tr></tbody></table>