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

Cloudflare Network Firewall has a new managed rule to help mitigate the Linux IPv4 TCP use-after-free vulnerability (CVE-2026-98432 ↗︎):

• Rule name: Block CVE-2026-98432 traffic
• Rule ID: 6a4df2bf984946a88c74b07349557e83

The rule is disabled by default. To use it:

1. Go to Networking > Firewall Policies > Managed Rulesets.
2. Enable the rule with action Log first.
3. Review traffic that matches the rule.
4. If the matching traffic is not expected for your environment, change the action to Block.

For more information on enabling managed rulesets, refer to Enable managed rulesets.

For more details about the vulnerability, including an agent assessment prompt and evidence sources, refer to the Cloudflare Radar Zero Wire briefing ↗︎.