CVE-2018-6922: Freebsd

Medium severity, CVSS 5.3. EPSS: 3.2% chance of exploitation in the next 30 days.

One of the data structures that holds TCP segments in all versions of FreeBSD prior to 11.2-RELEASE-p1, 11.1-RELEASE-p12, and 10.4-RELEASE-p10 uses an inefficient algorithm to reassemble the data. This causes the CPU time spent on segment processing to grow linearly with the number of segments in the reassembly queue. An attacker who has the ability to send TCP traffic to a victim system can degrade the victim system's network performance and/or consume excessive CPU by exploiting the inefficiency of TCP reassembly handling, with relatively small bandwidth cost.

Affected products

• Freebsd Freebsd: version 10.4 only; version 11.1 only; version 11.2 only

Published 2018-08-09. Last modified 2026-06-17.