CVE-2023-1206: Fedoraproject Fedora

Medium severity, CVSS 5.7. EPSS: 0.5% chance of exploitation in the next 30 days.

A hash collision flaw was found in the IPv6 connection lookup table in the Linux kernel’s IPv6 functionality when a user makes a new kind of SYN flood attack. A user located in the local network or with a high bandwidth connection can increase the CPU usage of the server that accepts IPV6 connections up to 95%.

Affected products

• Fedoraproject Fedora: version 38 only
• Linux Linux Kernel: before 6.5 (fixed in 6.5)
• Red Hat Enterprise Linux: version 8.0 only; version 9.0 only

Published 2023-06-30. Last modified 2026-06-17.