{"id":"CVE-2026-23274","title":"In the Linux kernel, the following vulnerability has been resolved:\n\nnetfilter: xt_IDLETIMER: reject rev0 reuse of ALARM timer labels\n\nIDLETIMER revision 0 rules reuse existing timers by label and always call\nmod_timer() on timer->timer.…","summary":"In the Linux kernel, the following vulnerability has been resolved:\n\nnetfilter: xt_IDLETIMER: reject rev0 reuse of ALARM timer labels\n\nIDLETIMER revision 0 rules reuse existing timers by label and always call\nmod_timer() on timer->timer.…","severity":"high","cvss":7.8,"cvssVector":"CVSS:3.1/AV:L/AC:L/PR:L/UI:N/S:U/C:H/I:H/A:H","vendor":"linux","product":"linux_kernel","affected":["linux_kernel >= 5.7, < 5.10.253","linux_kernel >= 5.11, < 5.15.203","linux_kernel >= 5.16, < 6.1.167","linux_kernel >= 6.2, < 6.6.130","linux_kernel >= 6.7, < 6.12.78","linux_kernel >= 6.13, < 6.18.19","linux_kernel >= 6.19, < 6.19.9","linux_kernel = 7.0"],"patched":["linux_kernel 6.19.9"],"published":"2026-03-20","updated":"2026-10-15","sourceUpdated":"2026-10-15T02:18:46.010","source":"NVD","sourceUrl":"https://nvd.nist.gov/vuln/detail/CVE-2026-23274","references":[{"url":"https://git.kernel.org/stable/c/144f88054ba0180467356f40895bd660b5dceeec","label":"416baaa9-dc9f-4396-8d5f-8c081fb06d67"},{"url":"https://git.kernel.org/stable/c/28c7cfaf0c0ab17cbd7754092116fd1af45271f9","label":"416baaa9-dc9f-4396-8d5f-8c081fb06d67"},{"url":"https://git.kernel.org/stable/c/329f0b9b48ee6ab59d1ab72fef55fe8c6463a6cf","label":"416baaa9-dc9f-4396-8d5f-8c081fb06d67"},{"url":"https://git.kernel.org/stable/c/32e937dc6e97f5ed3cdfe3fc0b2b19a05e23fa44","label":"416baaa9-dc9f-4396-8d5f-8c081fb06d67"},{"url":"https://git.kernel.org/stable/c/54080355999381fed4a26129579a5765bab87491","label":"416baaa9-dc9f-4396-8d5f-8c081fb06d67"},{"url":"https://git.kernel.org/stable/c/5e7ece24c5cb75a60402aad4d803c7898ea40aa9","label":"416baaa9-dc9f-4396-8d5f-8c081fb06d67"},{"url":"https://git.kernel.org/stable/c/f228b9ae2a7e84d1153616d8e71c4236cb1f1309","label":"416baaa9-dc9f-4396-8d5f-8c081fb06d67"},{"url":"https://git.kernel.org/stable/c/f5ef97c13165542480a6ffdbe6f09f40bbb7cbf1","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"},{"url":"https://cert-portal.siemens.com/productcert/html/ssa-784472.html","label":"0b142b55-0307-4c5a-b3c9-f314f3fb7c5e"},{"url":"https://security.access.redhat.com/data/csaf/v2/vex/2026/cve-2026-23274.json"},{"url":"https://access.redhat.com/security/cve/CVE-2026-23274"},{"url":"https://bugzilla.redhat.com/show_bug.cgi?id=2449572"},{"url":"https://www.cve.org/CVERecord?id=CVE-2026-23274"},{"url":"https://nvd.nist.gov/vuln/detail/CVE-2026-23274"},{"url":"https://lore.kernel.org/linux-cve-announce/2026032034-CVE-2026-23274-ba1d@gregkh/T"}],"tags":["nvd","cve.org","csaf","vex","red-hat","score-dispute"],"epss":0.0018,"epssPercentile":0.07458,"ingestedAt":"2026-09-08T15:33:26.993Z","ssvc":{"exploitation":"none","automatable":"no","technicalImpact":"total","timestamp":"2026-10-16T15:07:15.752483Z"},"cwe":["CWE-908"],"scores":{"nvd":7.8,"vendor":5.5,"cna":7.8},"slug":"CVE-2026-23274","body":"## Overview\n\nIn the Linux kernel, the following vulnerability has been resolved:\n\nnetfilter: xt_IDLETIMER: reject rev0 reuse of ALARM timer labels\n\nIDLETIMER revision 0 rules reuse existing timers by label and always call\nmod_timer() on timer->timer.\n\nIf the label was created first by revision 1 with XT_IDLETIMER_ALARM,\nthe object uses alarm timer semantics and timer->timer is never initialized.\nReusing that object from revision 0 causes mod_timer() on an uninitialized\ntimer_list, triggering debugobjects warnings and possible panic when\npanic_on_warn=1.\n\nFix this by rejecting revision 0 rule insertion when an existing timer with\nthe same label is of ALARM type.\n\n## Affected\n\n- `linux_kernel >= 5.7, < 5.10.253`\n- `linux_kernel >= 5.11, < 5.15.203`\n- `linux_kernel >= 5.16, < 6.1.167`\n- `linux_kernel >= 6.2, < 6.6.130`\n- `linux_kernel >= 6.7, < 6.12.78`\n- `linux_kernel >= 6.13, < 6.18.19`\n- `linux_kernel >= 6.19, < 6.19.9`\n- `linux_kernel = 7.0`\n\n## Remediation\n\nUpgrade past the affected range:\n\n- `linux_kernel 6.19.9`\n\n## Vendor advisories\n\n- **Red Hat VEX** · Moderate · affected: Red Hat Enterprise Linux 10, Red Hat Enterprise Linux 9 · no fix planned: Red Hat Enterprise Linux 10, Red Hat Enterprise Linux 9 · updated 2026-10-16 · [vex](https://security.access.redhat.com/data/csaf/v2/vex/2026/cve-2026-23274.json)","depth":"twilight","depthScore":43,"depthScoreParts":{"impact":42.9,"likelihood":0,"exploitation":0,"ransomware":0},"changes":[]}