CyberSecBulletin
CVE-2026-64574NVD status: Received

Linux: Use After Free

Published Updated By the CyberSecBulletin desk

CVE-2026-64574 is a high-severity use after free vulnerability in Linux, with a CVSS 3.1 base score of 7.8 out of 10. It can be exploited with local access to the system by an attacker with a low-privileged account, without any action from a user. The record lists versions 329589417214d3b7221432e5b266ed2bba7ff674, c57d97f381306bbfba174e8f708419e007824e0c, 0f7eaeb950adb77f71beb546e5ab30f90b41fe6f as the first without the flaw, so updating Linux to one of those releases or later removes the exposure. There is no confirmed exploitation so far. EPSS estimates a 0.16% chance of exploitation within 30 days, which is low compared with other CVEs.

Next patch cycle

High severity with no evidence of exploitation so far.

What to do

  1. Update Linux to 329589417214d3b7221432e5b266ed2bba7ff674 or c57d97f381306bbfba174e8f708419e007824e0c or 0f7eaeb950adb77f71beb546e5ab30f90b41fe6f or 901a73523e093beff123b54b1ceaf3113f18acc9, whichever matches your release line, or a later version.

Affected products and versions

VendorProductAffected versionsFixed in
LinuxLinux170cd6a66d9a164180eb4dc72d50afa6ce1ce566 up to, but not including, 329589417214d3b7221432e5b266ed2bba7ff674; 170cd6a66d9a164180eb4dc72d50afa6ce1ce566 up to, but not including, c57d97f381306bbfba174e8f708419e007824e0c; 170cd6a66d9a164180eb4dc72d50afa6ce1ce566 up to, but not including, 0f7eaeb950adb77f71beb546e5ab30f90b41fe6f; 170cd6a66d9a164180eb4dc72d50afa6ce1ce566 up to, but not including, 901a73523e093beff123b54b1ceaf3113f18acc9; 170cd6a66d9a164180eb4dc72d50afa6ce1ce566 up to, but not including, 952c02b33f56207a160421bcd61e7ac53c9c59ae; 6.4329589417214d3b7221432e5b266ed2bba7ff674, c57d97f381306bbfba174e8f708419e007824e0c, 0f7eaeb950adb77f71beb546e5ab30f90b41fe6f, 901a73523e093beff123b54b1ceaf3113f18acc9, 952c02b33f56207a160421bcd61e7ac53c9c59ae

Version data comes from the organisation that assigned the CVE. Confirm against the vendor advisory before deciding you are unaffected.

How the severity score breaks down

Attack vector
LocalThe attacker needs local access or must trick a user into running something.
Attack complexity
LowNo special conditions are needed; the attack works reliably.
Privileges required
LowA basic user account is enough.
User interaction
NoneNo action by a victim is required.
Scope
UnchangedImpact stays within the vulnerable component.
Confidentiality
HighAll data handled by the component can be read.
Integrity
HighData or code can be modified at will.
Availability
HighThe component can be taken down completely.

Vector: CVSS:3.1/AV:L/AC:L/PR:L/UI:N/S:U/C:H/I:H/A:H. Scored by CNA.

Official description

In the Linux kernel, the following vulnerability has been resolved: wifi: mac80211: tear down new links on vif update error path When ieee80211_vif_update_links() adds new links it allocates a link container for each and calls ieee80211_link_init() (which registers the per-link debugfs files with file->private_data pointing into the container) and ieee80211_link_setup(). If the subsequent drv_change_vif_links() fails, the error path restores the old pointers and jumps to 'free', which frees the new containers but never removes their debugfs entries or stops the links. The debugfs files survive with file->private_data dangling at the freed container, so a later open()+read() (e.g. link-1/txpower) dereferences freed memory in ieee80211_if_read_link(), a use-after-free. The removal path already dismantles links correctly via ieee80211_tear_down_links(), which removes each link's keys and debugfs entries and calls ieee80211_link_stop(); the add path on the error branch does not. Commit be1ba9ed221f ("wifi: mac80211: avoid weird state in error path") hardened this same error path for the link-removal case (new_links == 0) but left the newly-added links' teardown unaddressed. drv_change_vif_links() can fail at runtime on MLO drivers (internal allocation / queue / firmware command failures). Remove the new links' debugfs entries and stop them before freeing. BUG: KASAN: slab-use-after-free in ieee80211_if_read_link (net/mac80211/debugfs_netdev.c:127) Read of size 8 at addr ffff888011290000 by task exploit/145 Call Trace: ... ieee80211_if_read_link (net/mac80211/debugfs_netdev.c:127) short_proxy_read (fs/debugfs/file.c:373) vfs_read (fs/read_write.c:572) ksys_read (fs/read_write.c:716) do_syscall_64 (arch/x86/entry/syscall_64.c:94) entry_SYSCALL_64_after_hwframe (arch/x86/entry/entry_64.S:121) ... Oops: general protection fault, probably for non-canonical address 0xdffffc000000000a RIP: 0010:ieee80211_if_read_link (net/mac80211/debugfs_netdev.c:127) Kernel panic - not syncing: Fatal exception

Source: the CVE record as published by its numbering authority, via NVD and CVE.org.

The underlying weakness: Use After Free

The product reuses or references memory after it has been freed. At some point afterward, the memory may be allocated again and saved in another pointer, while the original pointer references a location somewhere within the new allocation. Any operations using the original pointer are no longer valid because the memory belongs to the code that operates on the new pointer.

How developers prevent this class of flaw

  • Choose a language that provides automatic memory management.
  • When freeing pointers, be sure to set them to NULL once they are freed. However, the utilization of multiple or complex data structures may lower the usefulness of this strategy.

More Use After Free vulnerabilities (CWE-416)

Timeline

  1. CVE record published.
  2. CISA published its SSVC assessment (exploitation: none, automatable: no, technical impact: total).
  3. Record last changed materially (score, affected products, status or references).

References

Recent Use After Free vulnerabilities

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