{"dataType":"CVE_RECORD","dataVersion":"5.2","cveMetadata":{"cveId":"CVE-2026-64574","assignerOrgId":"416baaa9-dc9f-4396-8d5f-8c081fb06d67","state":"PUBLISHED","assignerShortName":"Linux","dateReserved":"2026-07-19T15:36:31.797Z","datePublished":"2026-08-05T08:08:10.272Z","dateUpdated":"2026-08-17T04:57:54.008Z"},"containers":{"cna":{"providerMetadata":{"orgId":"416baaa9-dc9f-4396-8d5f-8c081fb06d67","shortName":"Linux","dateUpdated":"2026-08-17T04:57:54.008Z"},"descriptions":[{"lang":"en","value":"In the Linux kernel, the following vulnerability has been resolved:\n\nwifi: mac80211: tear down new links on vif update error path\n\nWhen ieee80211_vif_update_links() adds new links it allocates a link\ncontainer for each and calls ieee80211_link_init() (which registers the\nper-link debugfs files with file->private_data pointing into the container)\nand ieee80211_link_setup(). If the subsequent drv_change_vif_links() fails,\nthe error path restores the old pointers and jumps to 'free', which frees\nthe new containers but never removes their debugfs entries or stops the\nlinks. The debugfs files survive with file->private_data dangling at the\nfreed container, so a later open()+read() (e.g. link-1/txpower)\ndereferences freed memory in ieee80211_if_read_link(), a use-after-free.\n\nThe removal path already dismantles links correctly via\nieee80211_tear_down_links(), which removes each link's keys and debugfs\nentries and calls ieee80211_link_stop(); the add path on the error branch\ndoes not. Commit be1ba9ed221f (\"wifi: mac80211: avoid weird state in error\npath\") hardened this same error path for the link-removal case\n(new_links == 0) but left the newly-added links' teardown unaddressed.\n\ndrv_change_vif_links() can fail at runtime on MLO drivers (internal\nallocation / queue / firmware command failures).\n\nRemove the new links' debugfs entries and stop them before freeing.\n\n  BUG: KASAN: slab-use-after-free in ieee80211_if_read_link (net/mac80211/debugfs_netdev.c:127)\n  Read of size 8 at addr ffff888011290000 by task exploit/145\n  Call Trace:\n   ...\n   ieee80211_if_read_link (net/mac80211/debugfs_netdev.c:127)\n   short_proxy_read (fs/debugfs/file.c:373)\n   vfs_read (fs/read_write.c:572)\n   ksys_read (fs/read_write.c:716)\n   do_syscall_64 (arch/x86/entry/syscall_64.c:94)\n   entry_SYSCALL_64_after_hwframe (arch/x86/entry/entry_64.S:121)\n  ...\n  Oops: general protection fault, probably for non-canonical address 0xdffffc000000000a\n  RIP: 0010:ieee80211_if_read_link (net/mac80211/debugfs_netdev.c:127)\n  Kernel panic - not syncing: Fatal exception"}],"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 - The bug is reached via local nl80211 link updates (NL80211_CMD_ADD_LINK / ieee80211_vif_set_links → ieee80211_vif_update_links) and completed by a local debugfs open/read of the dangling per-link file, not by processing over-the-air frames alone.\nAC:L - An attacker can reliably force the error path by adding an MLO AP link whose MAC duplicates an existing link so ieee80211_check_dup_link_addrs() fails after ieee80211_link_init() already registered debugfs, then read the leftover file; no attacker-independent condition is required.\nPR:L - NL80211_CMD_ADD_LINK is gated by GENL_UNS_ADMIN_PERM (CAP_NET_ADMIN in the netns user_ns), which an unprivileged user can obtain via user/net namespaces or common WiFi management paths, so privileges are Low rather than init-namespace root.\nUI:N - The attacker issues the nl80211 ADD_LINK sequence and the subsequent debugfs read themselves; no separate victim action such as mounting a filesystem or opening a hostile file is required.\nS:U - The use-after-free and resulting kernel memory corruption stay within the host mac80211/debugfs authority and do not cross a VM, IOMMU, or other separate security boundary.\nC:H - Dangling debugfs file->private_data points at the freed link_container; reading it (ieee80211_if_read_link) is a slab use-after-free that can be reclaimed/sprayed for arbitrary kernel memory disclosure.\nI:H - The same freed link object is the debugfs private_data for readable/writable per-link files, so UAF reclaim enables attacker-controlled structure contents and control-flow hijack consistent with kernel UAF integrity High.\nA:H - The fix commit’s KASAN slab-use-after-free in ieee80211_if_read_link leads to a general protection fault and kernel panic, so availability impact is High even without full exploitation."}]}],"affected":[{"product":"Linux","vendor":"Linux","defaultStatus":"unaffected","repo":"https://git.kernel.org/pub/scm/linux/kernel/git/stable/linux.git","programFiles":["net/mac80211/link.c"],"versions":[{"version":"170cd6a66d9a164180eb4dc72d50afa6ce1ce566","lessThan":"329589417214d3b7221432e5b266ed2bba7ff674","status":"affected","versionType":"git"},{"version":"170cd6a66d9a164180eb4dc72d50afa6ce1ce566","lessThan":"c57d97f381306bbfba174e8f708419e007824e0c","status":"affected","versionType":"git"},{"version":"170cd6a66d9a164180eb4dc72d50afa6ce1ce566","lessThan":"0f7eaeb950adb77f71beb546e5ab30f90b41fe6f","status":"affected","versionType":"git"},{"version":"170cd6a66d9a164180eb4dc72d50afa6ce1ce566","lessThan":"901a73523e093beff123b54b1ceaf3113f18acc9","status":"affected","versionType":"git"},{"version":"170cd6a66d9a164180eb4dc72d50afa6ce1ce566","lessThan":"952c02b33f56207a160421bcd61e7ac53c9c59ae","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/link.c"],"versions":[{"version":"6.4","status":"affected"},{"version":"0","lessThan":"6.4","status":"unaffected","versionType":"semver"},{"version":"6.6.148","lessThanOrEqual":"6.6.*","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":"6.4","versionEndExcluding":"6.6.148"},{"vulnerable":true,"criteria":"cpe:2.3:o:linux:linux_kernel:*:*:*:*:*:*:*:*","versionStartIncluding":"6.4","versionEndExcluding":"6.12.101"},{"vulnerable":true,"criteria":"cpe:2.3:o:linux:linux_kernel:*:*:*:*:*:*:*:*","versionStartIncluding":"6.4","versionEndExcluding":"6.18.42"},{"vulnerable":true,"criteria":"cpe:2.3:o:linux:linux_kernel:*:*:*:*:*:*:*:*","versionStartIncluding":"6.4","versionEndExcluding":"7.1.6"},{"vulnerable":true,"criteria":"cpe:2.3:o:linux:linux_kernel:*:*:*:*:*:*:*:*","versionStartIncluding":"6.4","versionEndExcluding":"7.2"}]}]}],"references":[{"url":"https://git.kernel.org/stable/c/329589417214d3b7221432e5b266ed2bba7ff674"},{"url":"https://git.kernel.org/stable/c/c57d97f381306bbfba174e8f708419e007824e0c"},{"url":"https://git.kernel.org/stable/c/0f7eaeb950adb77f71beb546e5ab30f90b41fe6f"},{"url":"https://git.kernel.org/stable/c/901a73523e093beff123b54b1ceaf3113f18acc9"},{"url":"https://git.kernel.org/stable/c/952c02b33f56207a160421bcd61e7ac53c9c59ae"}],"title":"wifi: mac80211: tear down new links on vif update error path","x_generator":{"engine":"bippy-1.2.0"}}}}