Cloudflare Network Firewall - New managed rule to help mitigate CVE-2026-98432.

<p>Cloudflare Network Firewall has a new managed rule to help mitigate the Linux IPv4 TCP use-after-free vulnerability (<a href="https://www.cve.org/CVERecord?id=CVE-2026-98432" target="_blank" rel="noopener">CVE-2026-98432<span class="external-link"> ↗︎</span></a>):</p> <ul> <li><strong>Rule name:</strong> Block CVE-2026-98432 traffic</li> <li><strong>Rule ID:</strong> <code>6a4df2bf984946a88c74b07349557e83</code></li> </ul> <p>The rule is <strong>disabled by default</strong>. To use it:</p> <ol> <li>Go to <strong>Networking</strong> &gt; <strong>Firewall Policies</strong> &gt; <strong>Managed Rulesets</strong>.</li> <li>Enable the rule with action <strong>Log</strong> first.</li> <li>Review traffic that matches the rule.</li> <li>If the matching traffic is not expected for your environment, change the action to <strong>Block</strong>.</li> </ol> <p>For more information on enabling managed rulesets, refer to <a href="https://developers.cloudflare.com/cloudflare-network-firewall/how-to/enable-managed-rulesets/">Enable managed rulesets</a>.</p> <p>For more details about the vulnerability, including an agent assessment prompt and evidence sources, refer to the <a href="https://radar.cloudflare.com/security/zero-wire/linux-ipv4-tcp-use-after-free" target="_blank" rel="noopener">Cloudflare Radar Zero Wire briefing<span class="external-link"> ↗︎</span></a>.</p>