{"id":"CVE-2025-40171","title":"kernel: Kernel: Denial of Service in nvmet-fc due to resource leak (CVE-2025-40171)","summary":"A flaw was found in the Linux kernel's nvmet-fc component, which handles Non-Volatile Memory Express (NVMe) over Fibre Channel. A local attacker with low privileges could exploit a resource management issue. This flaw occurs when multiple …","severity":"medium","cvss":5.5,"cvssVector":"CVSS:3.1/AV:L/AC:L/PR:L/UI:N/S:U/C:N/I:N/A:H","cvssSource":"vendor","cwe":"CWE-772","vendor":"Red Hat","product":"Red Hat Enterprise Linux 9","affected":["enterprise_linux 10","enterprise_linux 8","enterprise_linux 9"],"published":"2025-11-12","updated":"2026-10-16","sourceUpdated":"2026-10-16T23:16:40+00:00","source":"CSAF","sourceUrl":"https://security.access.redhat.com/data/csaf/v2/vex/2025/cve-2025-40171.json","references":[{"url":"https://security.access.redhat.com/data/csaf/v2/vex/2025/cve-2025-40171.json"},{"url":"https://access.redhat.com/security/cve/CVE-2025-40171"},{"url":"https://bugzilla.redhat.com/show_bug.cgi?id=2414505"},{"url":"https://www.cve.org/CVERecord?id=CVE-2025-40171"},{"url":"https://nvd.nist.gov/vuln/detail/CVE-2025-40171"},{"url":"https://lore.kernel.org/linux-cve-announce/2025111259-CVE-2025-40171-0cb5@gregkh/T"},{"url":"https://git.kernel.org/stable/c/11269c08013f4ee8b8f5edc6c56700acb34092d0"},{"url":"https://git.kernel.org/stable/c/a28112cc55013cd8cbd5d36b5115a5b851151bd9"},{"url":"https://git.kernel.org/stable/c/060ecc81240ef9d60d9485a3a5eb55a0d6e7a25c"},{"url":"https://git.kernel.org/stable/c/7331925c247b03b7767b8cd93cfe1b7aa2377850"},{"url":"https://git.kernel.org/stable/c/7a619f8c869117ffed08365b377f66b7e1d941b4"},{"url":"https://git.kernel.org/stable/c/db5a5406fb7e5337a074385c7a3e53c77f2c1bd3"}],"tags":["csaf","vex","red-hat","cve.org","score-dispute"],"epss":0.00473,"epssPercentile":0.4071,"ssvc":{"exploitation":"none","automatable":"yes","technicalImpact":"partial","timestamp":"2026-10-15T21:57:33.774431Z"},"scores":{"vendor":5.5,"cna":7.5},"ingestedAt":"2026-10-15T22:48:25.549Z","slug":"CVE-2025-40171","body":"## Overview\n\nA flaw was found in the Linux kernel's nvmet-fc component, which handles Non-Volatile Memory Express (NVMe) over Fibre Channel. A local attacker with low privileges could exploit a resource management issue. This flaw occurs when multiple asynchronous commands are processed, leading to a leaked reference. This can result in a Denial of Service (DoS), making the system unavailable.\n\n## Vendor advisories\n\n- **Red Hat VEX** · Moderate · affected: Red Hat Enterprise Linux 10, Red Hat Enterprise Linux 8, Red Hat Enterprise Linux 9 · no fix planned: Red Hat Enterprise Linux 10, Red Hat Enterprise Linux 8, Red Hat Enterprise Linux 9 · updated 2026-10-16 · [vex](https://security.access.redhat.com/data/csaf/v2/vex/2025/cve-2025-40171.json)\n\n**kernel: Kernel: Denial of Service in nvmet-fc due to resource leak** — rated Moderate by Red Hat. Released 2025-11-12, updated 2026-10-16.\n\nAffected:\n\n- Red Hat Enterprise Linux 10\n- Red Hat Enterprise Linux 8\n- Red Hat Enterprise Linux 9\n\nNo fix planned:\n\n- Red Hat Enterprise Linux 10\n- Red Hat Enterprise Linux 8\n- Red Hat Enterprise Linux 9\n\nNot affected:\n\n- Red Hat Enterprise Linux 6\n- Red Hat Enterprise Linux 7\n\n## Remediation\n\nFix deferred\n\nWorkarounds / mitigations:\n\n- To mitigate this issue, prevent the 'nvmet-fc' kernel module from loading if NVMe over Fibre Channel functionality is not required. Create a file named `/etc/modprobe.d/blacklist-nvmet-fc.conf` with the following content:\n\n```\nblacklist nvmet-fc\ninstall nvmet-fc /bin/true\n```\n\nAfter creating the file, regenerate the initramfs and reboot the system for the changes to take effect. This may impact systems that rely on NVMe over Fibre Channel for storage operations. A system reboot is required for …","depth":"sunlit","depthScore":30,"depthScoreParts":{"impact":30.3,"likelihood":0.1,"exploitation":0,"ransomware":0},"changes":[{"seq":223597,"id":"CVE-2025-40171","ts":1792238333236,"field":"cvss","old":"7.5","new":"5.5"},{"seq":223596,"id":"CVE-2025-40171","ts":1792238333236,"field":"severity","old":"high","new":"medium"}]}