{ "schemaVersion": 1, "attribution": [ { "source": "CISA Known Exploited Vulnerabilities", "url": "https://www.cisa.gov/known-exploited-vulnerabilities-catalog", "licence": "US government work" }, { "source": "GitHub Advisory Database", "url": "https://github.com/advisories", "licence": "CC BY 4.0" }, { "source": "Have I Been Pwned", "url": "https://haveibeenpwned.com/", "licence": "CC BY 4.0" }, { "source": "CVE Program (CVE records)", "url": "https://www.cve.org/Legal/TermsOfUse", "licence": "CVE Terms of Use", "notice": "Copyright © 1999-2026, The MITRE Corporation. CVE is a trademark and the CVE logo is a registered trademark of The MITRE Corporation.", "terms": "CVE Usage: MITRE hereby grants you a perpetual, worldwide, non-exclusive, no-charge, royalty-free, irrevocable copyright license to reproduce, prepare derivative works of, publicly display, publicly perform, sublicense, and distribute Common Vulnerabilities and Exposures (CVE™). Any copy you make for such purposes is authorized provided that you reproduce MITRE's copyright designation and this license in any such copy." }, { "source": "FIRST EPSS", "url": "https://www.first.org/epss/", "licence": "free to use; FIRST requests attribution" } ], "record": { "id": "CVE-2026-68138", "sourceURL": "https://www.cve.org/CVERecord?id=CVE-2026-68138", "idYear": 2026, "status": "PUBLISHED", "publishedAt": "2026-08-10T11:59:01.744Z", "updatedAt": "2026-10-19T20:58:52.975Z", "importedAt": "2026-10-24T01:58:25.636Z", "snapshot": { "id": "cve_2026-10-24_midnight_baseline", "at": "2026-10-24T00:00:00.000Z", "source": "https://github.com/CVEProject/cvelistV5/releases/tag/cve_2026-10-24_0100Z" }, "facts": { "title": "net/sched: serialize qdisc_rtab_list against concurrent get/put", "summary": "In the Linux kernel, the following vulnerability has been resolved:\n\nnet/sched: serialize qdisc_rtab_list against concurrent get/put\n\nqdisc_get_rtab() and qdisc_put_rtab() mutate the process-global singly\nlinked list qdisc_rtab_list and a plain non-atomic 'int refcnt' with no\nlock. This was only safe because every caller historically held the RTNL\nmutex, which serialized all rate-table lookups, inserts and frees.\n\nThat invariant no longer holds. cls_flower sets\nTCF_PROTO_OPS_DOIT_UNLOCKED, so tc_new_tfilter() keeps rtnl_held == false\nfor it and sets TCA_ACT_FLAGS_NO_RTNL. That flag propagates through\ntcf_exts_validate_ex() -> tcf_action_init() -> tcf_action_init_1() ->\ntcf_police_init(), which calls qdisc_get_rtab()/qdisc_put_rtab() with the\nRTNL mutex NOT held. Two RTM_NEWTFILTER requests on different CPUs, each\nadding a flower filter with a police action carrying the same rate, then\nrace on qdisc_rtab_list and on the non-atomic refcnt, leading to a\nuse-after-free / double-free of the kmalloc-2k struct qdisc_rate_table.\nqdisc_rtab_list is a single global (not per-netns), so the corrupted\nobject is shared system-wide.\n\n BUG: KASAN: slab-use-after-free in qdisc_put_rtab+0x12f/0x160\n qdisc_put_rtab+0x12f/0x160\n tcf_police_init+0xda9/0x1590\n tcf_action_init_1+0x460/0x6b0\n tcf_action_init+0x439/0xa40\n tcf_exts_validate_ex+0x42d/0x550\n fl_change+0xddd/0x7da0\n tc_new_tfilter+0xaa7/0x2420\n rtnetlink_rcv_msg+0x95e/0xe90\n which belongs to the cache kmalloc-2k of size 2048\n\nProtect qdisc_rtab_list and the refcount with a dedicated spinlock. The\n(sleeping, GFP_KERNEL) allocation in qdisc_get_rtab() is performed before\ntaking the lock; if a concurrent inserter added an identical table in the\nmeantime the freshly allocated one is freed under the lock, so no\nduplicate is leaked. qdisc_put_rtab() now decrements the refcount and\nunlinks under the same lock.", "affected": [ { "vendor": "Linux", "product": "Linux", "defaultStatus": "unaffected", "versions": [ { "version": "470502de5bdb1ed0def643a4458593a40b8f6b66", "status": "affected", "versionType": "git", "lessThan": "1b050d09dd1a0ddae83bf012cf4956b7a960235f" }, { "version": "470502de5bdb1ed0def643a4458593a40b8f6b66", "status": "affected", "versionType": "git", "lessThan": "6e0241f6cbb149d926ee8efee2c734fea71452cf" }, { "version": "470502de5bdb1ed0def643a4458593a40b8f6b66", "status": "affected", "versionType": "git", "lessThan": "f93c89392bd3b180b5b7abc6fdae8e3dd667a313" }, { "version": "470502de5bdb1ed0def643a4458593a40b8f6b66", "status": "affected", "versionType": "git", "lessThan": "4131dd0b6f67acddd616ed7c244e1d3eedd46e7b" }, { "version": "470502de5bdb1ed0def643a4458593a40b8f6b66", "status": "affected", "versionType": "git", "lessThan": "d981098b76756ed71666a27518eeb69883657c43" }, { "version": "470502de5bdb1ed0def643a4458593a40b8f6b66", "status": "affected", "versionType": "git", "lessThan": "8ddc2eb0d2da9c83f54f1e5720525b461b8480c4" }, { "version": "470502de5bdb1ed0def643a4458593a40b8f6b66", "status": "affected", "versionType": "git", "lessThan": "fb29e1b41052488ee3f2d115d4a870497ebd7f7d" }, { "version": "470502de5bdb1ed0def643a4458593a40b8f6b66", "status": "affected", "versionType": "git", "lessThan": "f43ee0c0730d6191629b5ee1ceae27b1ebfdc047" } ] }, { "vendor": "Linux", "product": "Linux", "defaultStatus": "affected", "versions": [ { "version": "5.1", "status": "affected" }, { "version": "0", "status": "unaffected", "versionType": "semver", "lessThan": "5.1" }, { "version": "5.10.266", "status": "unaffected", "versionType": "semver", "lessThanOrEqual": "5.10.*" }, { "version": "5.15.217", "status": "unaffected", "versionType": "semver", "lessThanOrEqual": "5.15.*" }, { "version": "6.1.184", "status": "unaffected", "versionType": "semver", "lessThanOrEqual": "6.1.*" }, { "version": "6.6.153", "status": "unaffected", "versionType": "semver", "lessThanOrEqual": "6.6.*" }, { "version": "6.12.105", "status": "unaffected", "versionType": "semver", "lessThanOrEqual": "6.12.*" }, { "version": "6.18.46", "status": "unaffected", "versionType": "semver", "lessThanOrEqual": "6.18.*" }, { "version": "7.1.6", "status": "unaffected", "versionType": "semver", "lessThanOrEqual": "7.1.*" }, { "version": "7.2", "status": "unaffected", "versionType": "original_commit_for_fix", "lessThanOrEqual": "*" } ] } ] } } }