{"id":"CVE-2026-74401","title":"In the Linux kernel, the following vulnerability has been resolved:\n\ndlm: fix add msg handle in send_queue ordered\n\nIn a benchmark scenario triggering a lot of requests that triggers a lot\nof DLM messages on the network it can be that th…","summary":"In the Linux kernel, the following vulnerability has been resolved:\n\ndlm: fix add msg handle in send_queue ordered\n\nIn a benchmark scenario triggering a lot of requests that triggers a lot\nof DLM messages on the network it can be that th…","severity":"critical","cvss":9.8,"cvssVector":"CVSS:3.1/AV:N/AC:L/PR:N/UI:N/S:U/C:H/I:H/A:H","cwe":["CWE-416"],"vendor":"Red Hat","product":"Red Hat Enterprise Linux 9","affected":["enterprise_linux 6","enterprise_linux 9"],"published":"2026-08-15","updated":"2026-10-16","sourceUpdated":"2026-10-16T20:17:25.567","source":"NVD","sourceUrl":"https://nvd.nist.gov/vuln/detail/CVE-2026-74401","references":[{"url":"https://git.kernel.org/stable/c/4d45250b1d22960f86d83245be188b16e456218b","label":"416baaa9-dc9f-4396-8d5f-8c081fb06d67"},{"url":"https://git.kernel.org/stable/c/6369619f1b665f12d8c99cc6ff733c64eb08b22e","label":"416baaa9-dc9f-4396-8d5f-8c081fb06d67"},{"url":"https://git.kernel.org/stable/c/712714f818d83373847874ab0f8e426be79296cf","label":"416baaa9-dc9f-4396-8d5f-8c081fb06d67"},{"url":"https://git.kernel.org/stable/c/ae9e534e502a0f48c12baf83608c5de0ff0eab11","label":"416baaa9-dc9f-4396-8d5f-8c081fb06d67"},{"url":"https://git.kernel.org/stable/c/d2248cb70c070f8f04762872772e155b59016f17","label":"416baaa9-dc9f-4396-8d5f-8c081fb06d67"},{"url":"https://security.access.redhat.com/data/csaf/v2/vex/2026/cve-2026-74401.json"},{"url":"https://access.redhat.com/security/cve/CVE-2026-74401"},{"url":"https://bugzilla.redhat.com/show_bug.cgi?id=2516864"},{"url":"https://www.cve.org/CVERecord?id=CVE-2026-74401"},{"url":"https://nvd.nist.gov/vuln/detail/CVE-2026-74401"},{"url":"https://kernelcve.org/list/?q=CVE-2026-74401"},{"url":"https://lore.kernel.org/linux-cve-announce/2026081509-CVE-2026-74401-2c5f@gregkh/T"}],"tags":["nvd","csaf","vex","red-hat","cve.org","score-dispute"],"epss":0.00652,"epssPercentile":0.51054,"ssvc":{"exploitation":"none","automatable":"yes","technicalImpact":"total","timestamp":"2026-10-16T18:55:33.158512Z"},"scores":{"nvd":9.8,"vendor":5.3,"cna":9.8},"ingestedAt":"2026-10-16T19:46:24.368Z","slug":"CVE-2026-74401","body":"## Overview\n\nIn the Linux kernel, the following vulnerability has been resolved:\n\ndlm: fix add msg handle in send_queue ordered\n\nIn a benchmark scenario triggering a lot of requests that triggers a lot\nof DLM messages on the network it can be that the mh->seq is not ordered\naccording the oldest seq number. This ordering is required by\ndlm_receive_ack as \"before(mh->seq, seq)\" will stop to check for older\nsequence numbers that are ordered in the tail of \"node->send_queue\".\n\nThe side effects of not having it correct ordered regarding\n\"before(mh->seq, seq)\" are refcounting issues and use-after free.\n\nI only was able to reproduce this issue in a experimental DLM branch\nand a user space DLM benchmark that uses io_uring. After changing this I\ndon't experienced any refcounting with the sending buffer issues anymore.\n\n## Remediation\n\nRefer to the linked advisories for vendor-supplied fixes and affected version ranges.\n\n## Vendor advisories\n\n- **Red Hat VEX** · Moderate · affected: Red Hat Enterprise Linux 6, Red Hat Enterprise Linux 9 · no fix planned: Red Hat Enterprise Linux 6, Red Hat Enterprise Linux 9 · updated 2026-10-26 · [vex](https://security.access.redhat.com/data/csaf/v2/vex/2026/cve-2026-74401.json)","depth":"midnight","depthScore":54,"depthScoreParts":{"impact":53.9,"likelihood":0.1,"exploitation":0,"ransomware":0},"changes":[{"seq":230388,"id":"CVE-2026-74401","ts":1793134634849,"field":"cvss","old":"5.3","new":"9.8"},{"seq":230387,"id":"CVE-2026-74401","ts":1793134634849,"field":"severity","old":"medium","new":"critical"},{"seq":229378,"id":"CVE-2026-74401","ts":1793019723011,"field":"cvss","old":"9.8","new":"5.3"},{"seq":229377,"id":"CVE-2026-74401","ts":1793019723011,"field":"severity","old":"critical","new":"medium"}]}