{"id":"CVE-2026-64574","published":"2026-08-05T08:16:37.203","lastModified":"2026-08-08T15:16:32.263","description":"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","cvssScore":7.8,"cvssSeverity":"HIGH","cvssVector":"CVSS:3.1/AV:L/AC:L/PR:L/UI:N/S:U/C:H/I:H/A:H","cwes":[],"vendors":[],"products":[],"references":[{"url":"https://git.kernel.org/stable/c/0f7eaeb950adb77f71beb546e5ab30f90b41fe6f","tags":[]},{"url":"https://git.kernel.org/stable/c/329589417214d3b7221432e5b266ed2bba7ff674","tags":[]},{"url":"https://git.kernel.org/stable/c/901a73523e093beff123b54b1ceaf3113f18acc9","tags":[]},{"url":"https://git.kernel.org/stable/c/952c02b33f56207a160421bcd61e7ac53c9c59ae","tags":[]},{"url":"https://git.kernel.org/stable/c/c57d97f381306bbfba174e8f708419e007824e0c","tags":[]}],"exploitRefs":[],"hasPoc":false,"ai":{"summary":"The flaw involves a use-after-free vulnerability in the Linux kernel's mac80211 subsystem when adding new links during vif update. This can lead to dereferencing freed memory via debugfs files.","exploitability":"Exploitation requires runtime failure of drv_change_vif_links() on MLO drivers, making it moderately difficult but feasible with specific conditions.","blast_radius":"If exploited, this could result in potential kernel crashes or privilege escalation due to memory corruption.","remediation":"Apply the patch from commit be1ba9ed221f to ensure new links' debugfs entries and links are properly removed before freeing containers.","tags":["kernel","memory-corruption","use-after-free"],"model":"qwen2.5:7b-instruct","analyzedAt":"2026-08-11T06:52:20.155Z"}}