CVE-2026-43029

Name of the Vulnerable Software and Affected Versions Linux kernel version 6.19.0-rc8

Description A soft lockup can occur in the mptcp recvmsg() function. When receiving data with MSG PEEK and MSG WAITALL flags, the socket buffer (skb) is not removed from the sk receive queue. This causes the sk wait data() function to continuously find available data without performing an actual wait, resulting in an infinite loop and a system soft lockup.

Recommendations Update the Linux kernel to a version where the mptcp recvmsg() function has been patched to include a last parameter for tracking the last peeked socket buffer.