CVE-2026-74401: Linux

Critical severity, CVSS 9.8. EPSS: 0.7% chance of exploitation in the next 30 days.

In the Linux kernel, the following vulnerability has been resolved: dlm: fix add msg handle in send_queue ordered In a benchmark scenario triggering a lot of requests that triggers a lot of DLM messages on the network it can be that the mh->seq is not ordered according the oldest seq number. This ordering is required by dlm_receive_ack as "before(mh->seq, seq)" will stop to check for older sequence numbers that are ordered in the tail of "node->send_queue". The side effects of not having it correct ordered regarding "before(mh->seq, seq)" are refcounting issues and use-after free. I only was able to reproduce this issue in a experimental DLM branch and a user space DLM benchmark that uses io_uring. After changing this I don't experienced any refcounting with the sending buffer issues anymore.

Affected products

• Linux Linux: from 5.14, before 6.6.145 (fixed in 6.6.145); from 6.7, before 6.12.97 (fixed in 6.12.97); from 6.13, before 6.18.40 (fixed in 6.18.40); from 6.19, before 7.1.5 (fixed in 7.1.5)

Published 2026-08-15. Last modified 2026-08-17.