{"id":"AZL-94467","summary":"CVE-2026-64574 affecting package kernel for versions less than 6.6.150.1-1","details":"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-\u003eprivate_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-\u003eprivate_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","modified":"2026-08-28T17:48:06.831975055Z","published":"2026-08-05T08:16:37Z","upstream":["CVE-2026-64574"],"references":[{"type":"WEB","url":"https://nvd.nist.gov/vuln/detail/CVE-2026-64574"}],"affected":[{"package":{"name":"kernel","ecosystem":"Azure Linux:3","purl":"pkg:rpm/azure-linux/kernel"},"ranges":[{"type":"ECOSYSTEM","events":[{"introduced":"0"},{"fixed":"6.6.150.1-1"}]}],"database_specific":{"source":"https://github.com/microsoft/AzureLinuxVulnerabilityData/blob/main/osv/AZL-94467.json"}}],"schema_version":"1.9.0"}