{ "dataType": "CVE_RECORD", "dataVersion": "5.2", "cveMetadata": { "cveId": "CVE-2026-64570", "assignerOrgId": "416baaa9-dc9f-4396-8d5f-8c081fb06d67", "state": "PUBLISHED", "assignerShortName": "Linux", "dateReserved": "2026-07-19T15:36:31.797Z", "datePublished": "2026-08-05T08:08:07.855Z", "dateUpdated": "2026-08-17T04:57:49.594Z" }, "containers": { "cna": { "providerMetadata": { "orgId": "416baaa9-dc9f-4396-8d5f-8c081fb06d67", "shortName": "Linux", "dateUpdated": "2026-08-17T04:57:49.594Z" }, "descriptions": [ { "lang": "en", "value": "In the Linux kernel, the following vulnerability has been resolved:\n\nwifi: mac80211: fix fils_discovery double free on alloc failure\n\nieee80211_set_fils_discovery() calls kfree_rcu() on the old template\nbefore allocating the replacement. If the kzalloc() then fails, it\nreturns -ENOMEM while link->u.ap.fils_discovery still points at the\nobject already queued for freeing. A later update or AP teardown\n(ieee80211_stop_ap()) re-queues that same rcu_head; the second free is\ncaught by KASAN when the RCU sheaf is processed in softirq:\n\n BUG: KASAN: double-free in rcu_free_sheaf (mm/slub.c:5850)\n Free of addr ffff88800c065280 by task swapper/0/0\n ...\n __rcu_free_sheaf_prepare (mm/slub.c:2634 mm/slub.c:2940)\n rcu_free_sheaf (mm/slub.c:5850)\n rcu_core (kernel/rcu/tree.c:2617 kernel/rcu/tree.c:2869)\n handle_softirqs (kernel/softirq.c:622)\n The buggy address belongs to the cache kmalloc-96 of size 96\n\nQueue the old object for kfree_rcu() only after the new one is published,\nmatching ieee80211_set_probe_resp() and ieee80211_set_s1g_short_beacon()." } ], "metrics": [ { "cvssV3_1": { "version": "3.1", "vectorString": "CVSS:3.1/AV:L/AC:L/PR:L/UI:N/S:U/C:H/I:H/A:H", "baseScore": 7.8, "baseSeverity": "HIGH" }, "scenarios": [ { "lang": "en", "value": "AV:L - Triggered only via local nl80211 SoftAP config (NL80211_CMD_START_AP/SET_BEACON → ieee80211_set_fils_discovery), not by processing over-the-air WiFi frames or remote packets.\nAC:L - The attacker fully controls the SET_BEACON/STOP_AP sequence and can force the GFP_KERNEL kzalloc failure (e.g. memory pressure/memcg) with an attacker-chosen template size; no race or condition outside attacker influence is required.\nPR:L - START_AP and SET_BEACON use GENL_UNS_ADMIN_PERM (CAP_NET_ADMIN in the wiphy netns user_ns). Per CNA guidance that capability via user namespaces scores Low, not init-namespace root High.\nUI:N - The attacker issues the nl80211 commands to set FILS discovery and later tear down or update the AP; no separate victim action is required.\nS:U - Impact stays inside the host kernel mac80211 heap (local privilege-escalation class) and does not cross a VM, IOMMU, or other separate security authority.\nC:H - After the failed alloc the dangling fils_discovery pointer can be read via ieee80211_get_fils_discovery_tmpl and the object is double-freed; double-free/UAF enables heap reuse and arbitrary kernel memory disclosure.\nI:H - Double-free of the attacker-sized kmalloc FILS template (and subsequent stop_ap/update re-free) is classic heap corruption enabling spray/arbitrary-write and control-flow hijack primitives.\nA:H - The bug is a KASAN-confirmed double-free in rcu_free_sheaf softirq processing and can oops/panic the kernel, fully denying availability." } ] } ], "affected": [ { "product": "Linux", "vendor": "Linux", "defaultStatus": "unaffected", "repo": "https://git.kernel.org/pub/scm/linux/kernel/git/stable/linux.git", "programFiles": [ "net/mac80211/cfg.c" ], "versions": [ { "version": "3b1c256eb4aedfc71dd97d5951ccff824b41d628", "lessThan": "e2c55079155a953db669ca1986a985fa286bad95", "status": "affected", "versionType": "git" }, { "version": "3b1c256eb4aedfc71dd97d5951ccff824b41d628", "lessThan": "5baaa1042f71dd4b8e418f2cdd516808702d229b", "status": "affected", "versionType": "git" }, { "version": "3b1c256eb4aedfc71dd97d5951ccff824b41d628", "lessThan": "1981fba71797ec95e6755fb882cad88899a2a84f", "status": "affected", "versionType": "git" }, { "version": "3b1c256eb4aedfc71dd97d5951ccff824b41d628", "lessThan": "286e52a799fa158bdbd77da1426c4d93f9a6e7ad", "status": "affected", "versionType": "git" } ] }, { "product": "Linux", "vendor": "Linux", "defaultStatus": "affected", "repo": "https://git.kernel.org/pub/scm/linux/kernel/git/stable/linux.git", "programFiles": [ "net/mac80211/cfg.c" ], "versions": [ { "version": "6.7", "status": "affected" }, { "version": "0", "lessThan": "6.7", "status": "unaffected", "versionType": "semver" }, { "version": "6.12.101", "lessThanOrEqual": "6.12.*", "status": "unaffected", "versionType": "semver" }, { "version": "6.18.42", "lessThanOrEqual": "6.18.*", "status": "unaffected", "versionType": "semver" }, { "version": "7.1.6", "lessThanOrEqual": "7.1.*", "status": "unaffected", "versionType": "semver" }, { "version": "7.2", "lessThanOrEqual": "*", "status": "unaffected", "versionType": "original_commit_for_fix" } ] } ], "cpeApplicability": [ { "nodes": [ { "operator": "OR", "negate": false, "cpeMatch": [ { "vulnerable": true, "criteria": "cpe:2.3:o:linux:linux_kernel:*:*:*:*:*:*:*:*", "versionStartIncluding": "6.7", "versionEndExcluding": "6.12.101" }, { "vulnerable": true, "criteria": "cpe:2.3:o:linux:linux_kernel:*:*:*:*:*:*:*:*", "versionStartIncluding": "6.7", "versionEndExcluding": "6.18.42" }, { "vulnerable": true, "criteria": "cpe:2.3:o:linux:linux_kernel:*:*:*:*:*:*:*:*", "versionStartIncluding": "6.7", "versionEndExcluding": "7.1.6" }, { "vulnerable": true, "criteria": "cpe:2.3:o:linux:linux_kernel:*:*:*:*:*:*:*:*", "versionStartIncluding": "6.7", "versionEndExcluding": "7.2" } ] } ] } ], "references": [ { "url": "https://git.kernel.org/stable/c/e2c55079155a953db669ca1986a985fa286bad95" }, { "url": "https://git.kernel.org/stable/c/5baaa1042f71dd4b8e418f2cdd516808702d229b" }, { "url": "https://git.kernel.org/stable/c/1981fba71797ec95e6755fb882cad88899a2a84f" }, { "url": "https://git.kernel.org/stable/c/286e52a799fa158bdbd77da1426c4d93f9a6e7ad" } ], "title": "wifi: mac80211: fix fils_discovery double free on alloc failure", "x_generator": { "engine": "bippy-1.2.0" } } } }