CVE-2019-5598: In FreeBSD 11.3-PRERELEASE before r345378, 12.0-STABLE before r345377, 11.2-RELEASE before 11.2-RELEASE-p10...

Security readout for executives and security teams

This flaw can let specially crafted ICMP or ICMPv6 traffic pass through FreeBSD pf firewall rules that should block it. The business risk is highest where affected FreeBSD systems use pf as a network boundary or segmentation control. The sources do not show CISA KEV listing or confirmed active exploitation. Exposure is limited to affected FreeBSD 11.2, 12.0, 11.3-PRERELEASE, and 12.0-STABLE builds using pf to enforce packet filtering. Downstream products may be affected only where their vendor advisories confirm FreeBSD pf exposure. Prioritize remediation where FreeBSD pf protects sensitive internal hosts or acts as a boundary firewall. Older unsupported or appliance-managed systems deserve extra attention because the flaw weakens a network control rather than only a local component. Mitigation focus: Upgrade FreeBSD to the fixed patch level or revision named by FreeBSD.; Apply downstream vendor guidance for NetApp, Oracle, or appliance distributions.; Prioritize systems where pf enforces perimeter or segmentation policy..

Prepared

Jun 6, 2026, 20:55 UTC (UTC+00:00)

Generated from the cited source records. This long-tail analysis has not been individually reviewed by a named human.