{"id":"CVE-2026-31418","title":"In the Linux kernel, the following vulnerability has been resolved:\n\nnetfilter: ipset: drop logically empty buckets in mtype_del\n\nmtype_del() counts empty slots below n->pos in k, but it only drops the\nbucket when both n->pos and k are z…","summary":"In the Linux kernel, the following vulnerability has been resolved:\n\nnetfilter: ipset: drop logically empty buckets in mtype_del\n\nmtype_del() counts empty slots below n->pos in k, but it only drops the\nbucket when both n->pos and k are z…","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","vendor":"linux","product":"linux_kernel","affected":["linux_kernel >= 5.4.24, < 5.5","linux_kernel >= 5.5.8, < 5.6","linux_kernel >= 5.6.1, < 5.10.253","linux_kernel >= 5.11, < 5.15.203","linux_kernel >= 5.16, < 6.1.168","linux_kernel >= 6.2, < 6.6.134","linux_kernel >= 6.7, < 6.12.81","linux_kernel >= 6.13, < 6.18.22","linux_kernel >= 6.19, < 6.19.12","linux_kernel = 5.6","linux_kernel = 7.0"],"patched":["linux_kernel 6.19.12"],"published":"2026-04-13","updated":"2026-10-15","sourceUpdated":"2026-10-15T02:19:03.653","source":"NVD","sourceUrl":"https://nvd.nist.gov/vuln/detail/CVE-2026-31418","references":[{"url":"https://git.kernel.org/stable/c/58f3a14826d4e6b0d5421f1a64be280b48601ea2","label":"416baaa9-dc9f-4396-8d5f-8c081fb06d67"},{"url":"https://git.kernel.org/stable/c/68ca0eea0af02bed36c5e2c13e9fa1647c31a7d4","label":"416baaa9-dc9f-4396-8d5f-8c081fb06d67"},{"url":"https://git.kernel.org/stable/c/6cea34d7ec6829b62f521a37a287f670144a2233","label":"416baaa9-dc9f-4396-8d5f-8c081fb06d67"},{"url":"https://git.kernel.org/stable/c/9862ef9ab0a116c6dca98842aab7de13a252ae02","label":"416baaa9-dc9f-4396-8d5f-8c081fb06d67"},{"url":"https://git.kernel.org/stable/c/ad92ee87462f9a3061361d392e9dbfe2e5c1c9fb","label":"416baaa9-dc9f-4396-8d5f-8c081fb06d67"},{"url":"https://git.kernel.org/stable/c/b7eef00f08b92b0b9efe8ae0df6d0005e6199323","label":"416baaa9-dc9f-4396-8d5f-8c081fb06d67"},{"url":"https://git.kernel.org/stable/c/c098ff857e7ca923539164af5b3c2fe3e8f8afaf","label":"416baaa9-dc9f-4396-8d5f-8c081fb06d67"},{"url":"https://git.kernel.org/stable/c/ceacaa76f221a6577aba945bb8873c2e640aeba4","label":"416baaa9-dc9f-4396-8d5f-8c081fb06d67"},{"url":"https://cert-portal.siemens.com/productcert/html/ssa-019113.html","label":"0b142b55-0307-4c5a-b3c9-f314f3fb7c5e"},{"url":"https://cert-portal.siemens.com/productcert/html/ssa-082556.html","label":"0b142b55-0307-4c5a-b3c9-f314f3fb7c5e"},{"url":"https://cert-portal.siemens.com/productcert/html/ssa-457936.html","label":"0b142b55-0307-4c5a-b3c9-f314f3fb7c5e"}],"tags":["nvd","cve.org"],"epss":0.0012,"epssPercentile":0.01835,"ingestedAt":"2026-09-08T15:33:26.991Z","slug":"CVE-2026-31418","body":"## Overview\n\nIn the Linux kernel, the following vulnerability has been resolved:\n\nnetfilter: ipset: drop logically empty buckets in mtype_del\n\nmtype_del() counts empty slots below n->pos in k, but it only drops the\nbucket when both n->pos and k are zero. This misses buckets whose live\nentries have all been removed while n->pos still points past deleted slots.\n\nTreat a bucket as empty when all positions below n->pos are unused and\nrelease it directly instead of shrinking it further.\n\n## Affected\n\n- `linux_kernel >= 5.4.24, < 5.5`\n- `linux_kernel >= 5.5.8, < 5.6`\n- `linux_kernel >= 5.6.1, < 5.10.253`\n- `linux_kernel >= 5.11, < 5.15.203`\n- `linux_kernel >= 5.16, < 6.1.168`\n- `linux_kernel >= 6.2, < 6.6.134`\n- `linux_kernel >= 6.7, < 6.12.81`\n- `linux_kernel >= 6.13, < 6.18.22`\n- `linux_kernel >= 6.19, < 6.19.12`\n- `linux_kernel = 5.6`\n- `linux_kernel = 7.0`\n\n## Remediation\n\nUpgrade past the affected range:\n\n- `linux_kernel 6.19.12`","depth":"sunlit","depthScore":30,"depthScoreParts":{"impact":30.3,"likelihood":0,"exploitation":0,"ransomware":0},"changes":[{"seq":221695,"id":"CVE-2026-31418","ts":1792035328864,"field":"cvss","old":null,"new":"5.5"},{"seq":221694,"id":"CVE-2026-31418","ts":1792035328864,"field":"severity","old":"none","new":"medium"}]}