{"id":"CVE-2026-22999","title":"net/sched: sch_qfq: do not free existing class in qfq_change_class()","summary":"In the Linux kernel, the following vulnerability has been resolved:\n\nnet/sched: sch_qfq: do not free existing class in qfq_change_class()\n\nFixes qfq_change_class() error case.\n\ncl->qdisc and cl should only be freed if a new class and qdi…","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","cvssSource":"cna","vendor":"Linux","product":"Linux","affected":["Linux >= 462dbc9101acd38e92eda93c0726857517a24bbd < 2a64fb9b47afffeb5dbab5fd3a518e1436dcc90e","Linux >= 462dbc9101acd38e92eda93c0726857517a24bbd < cff6cd703f41d8071995956142729e4bba160363","Linux >= 462dbc9101acd38e92eda93c0726857517a24bbd < f06f7635499bc806cbe2bbc8805c7cef8b1edddf","Linux >= 462dbc9101acd38e92eda93c0726857517a24bbd < 0a234660dc70ce45d771cbc76b20d925b73ec160","Linux >= 462dbc9101acd38e92eda93c0726857517a24bbd < 362e269bb03f7076ba9990e518aeddb898232e50","Linux >= 462dbc9101acd38e92eda93c0726857517a24bbd < e9d8f11652fa08c647bf7bba7dd8163241a332cd","Linux >= 462dbc9101acd38e92eda93c0726857517a24bbd < 3879cffd9d07aa0377c4b8835c4f64b4fb24ac78","Linux 3.8"],"ssvc":{"exploitation":"none","automatable":"no","technicalImpact":"total","timestamp":"2026-06-16T20:35:55.025194Z"},"published":"2026-01-25","updated":"2026-10-19","sourceUpdated":"2026-10-19T18:25:27.014Z","source":"CVEORG","sourceUrl":"https://www.cve.org/CVERecord?id=CVE-2026-22999","references":[{"url":"https://git.kernel.org/stable/c/2a64fb9b47afffeb5dbab5fd3a518e1436dcc90e"},{"url":"https://git.kernel.org/stable/c/cff6cd703f41d8071995956142729e4bba160363"},{"url":"https://git.kernel.org/stable/c/f06f7635499bc806cbe2bbc8805c7cef8b1edddf"},{"url":"https://git.kernel.org/stable/c/0a234660dc70ce45d771cbc76b20d925b73ec160"},{"url":"https://git.kernel.org/stable/c/362e269bb03f7076ba9990e518aeddb898232e50"},{"url":"https://git.kernel.org/stable/c/e9d8f11652fa08c647bf7bba7dd8163241a332cd"},{"url":"https://git.kernel.org/stable/c/3879cffd9d07aa0377c4b8835c4f64b4fb24ac78"}],"tags":["cve.org"],"epss":0.00239,"epssPercentile":0.13989,"ingestedAt":"2026-10-19T18:35:50.111Z","slug":"CVE-2026-22999","body":"## Overview\n\nIn the Linux kernel, the following vulnerability has been resolved:\n\nnet/sched: sch_qfq: do not free existing class in qfq_change_class()\n\nFixes qfq_change_class() error case.\n\ncl->qdisc and cl should only be freed if a new class and qdisc\nwere allocated, or we risk various UAF.\n\n## Affected\n\n- `Linux >= 462dbc9101acd38e92eda93c0726857517a24bbd < 2a64fb9b47afffeb5dbab5fd3a518e1436dcc90e`\n- `Linux >= 462dbc9101acd38e92eda93c0726857517a24bbd < cff6cd703f41d8071995956142729e4bba160363`\n- `Linux >= 462dbc9101acd38e92eda93c0726857517a24bbd < f06f7635499bc806cbe2bbc8805c7cef8b1edddf`\n- `Linux >= 462dbc9101acd38e92eda93c0726857517a24bbd < 0a234660dc70ce45d771cbc76b20d925b73ec160`\n- `Linux >= 462dbc9101acd38e92eda93c0726857517a24bbd < 362e269bb03f7076ba9990e518aeddb898232e50`\n- `Linux >= 462dbc9101acd38e92eda93c0726857517a24bbd < e9d8f11652fa08c647bf7bba7dd8163241a332cd`\n- `Linux >= 462dbc9101acd38e92eda93c0726857517a24bbd < 3879cffd9d07aa0377c4b8835c4f64b4fb24ac78`\n- `Linux 3.8`\n\n## Remediation\n\nRefer to the linked advisories for vendor-supplied fixes and affected version ranges.","depth":"twilight","depthScore":43,"depthScoreParts":{"impact":42.9,"likelihood":0,"exploitation":0,"ransomware":0},"changes":[]}