Linux: Use After Free
CVE-2026-68414 is a high-severity use after free vulnerability in Linux, with a CVSS 3.1 base score of 7.5 out of 10. It can be exploited from the same local network by an unauthenticated attacker, without any action from a user. The record lists versions c0fa1f3a4b021a5c6373169fd6c9bb4261d676a0, b51b42b974461fd0f688baad85f10e2b8ab215c5, 3368457b4871ae8f0f88d19c9a3e6270e850ede6 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 0.23% chance of exploitation within 30 days, which is low compared with other CVEs.
High severity with no evidence of exploitation so far.
What to do
- Update Linux to c0fa1f3a4b021a5c6373169fd6c9bb4261d676a0 or b51b42b974461fd0f688baad85f10e2b8ab215c5 or 3368457b4871ae8f0f88d19c9a3e6270e850ede6 or 308ffdf575560d7e7b8b21f1e3ca6276630f73bf, whichever matches your release line, or a later version.
Affected products and versions
| Vendor | Product | Affected versions | Fixed in |
|---|---|---|---|
| Linux | Linux | 807f8a8c300435d5483e8d78df9dcdbc27333166 up to, but not including, c0fa1f3a4b021a5c6373169fd6c9bb4261d676a0; 807f8a8c300435d5483e8d78df9dcdbc27333166 up to, but not including, b51b42b974461fd0f688baad85f10e2b8ab215c5; 807f8a8c300435d5483e8d78df9dcdbc27333166 up to, but not including, 3368457b4871ae8f0f88d19c9a3e6270e850ede6; 807f8a8c300435d5483e8d78df9dcdbc27333166 up to, but not including, 308ffdf575560d7e7b8b21f1e3ca6276630f73bf; 807f8a8c300435d5483e8d78df9dcdbc27333166 up to, but not including, 9293574ac208d18c11073538851fb69355beb3b5; 807f8a8c300435d5483e8d78df9dcdbc27333166 up to, but not including, b119c70b24776c8ab2a2c0515397b3b0ad4e66cd; 807f8a8c300435d5483e8d78df9dcdbc27333166 up to, but not including, edf0730be33696a1bd142792830d392129e495cc; 3.0 | c0fa1f3a4b021a5c6373169fd6c9bb4261d676a0, b51b42b974461fd0f688baad85f10e2b8ab215c5, 3368457b4871ae8f0f88d19c9a3e6270e850ede6, 308ffdf575560d7e7b8b21f1e3ca6276630f73bf, 9293574ac208d18c11073538851fb69355beb3b5, b119c70b24776c8ab2a2c0515397b3b0ad4e66cd |
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
- AdjacentThe attacker must be on the same local network segment.
- Attack complexity
- HighSuccess depends on conditions outside the attacker's control.
- Privileges required
- NoneNo account or login is needed.
- 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:A/AC:H/PR:N/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: cfg80211: cancel sched scan results work on unregister cfg80211_sched_scan_results() can queue rdev->sched_scan_res_wk from a driver result notification while a scheduled scan request is present. The work callback recovers the containing cfg80211_registered_device and then locks the wiphy and walks the scheduled-scan request list. wiphy_unregister() already makes the wiphy unreachable and drains rdev work items before cfg80211_dev_free() can release the object, but it does not drain sched_scan_res_wk. A queued or running result work item can therefore cross the unregister/free boundary and access freed rdev state. The buggy scenario involves two paths, with each column showing the order within that path: scheduled-scan result path: unregister/free path: 1. cfg80211_sched_scan_results() 1. interface teardown stops and queues rdev->sched_scan_res_wk. removes the scheduled scan request. 2. cfg80211_wq starts the work 2. wiphy_unregister() drains other item and recovers rdev. rdev work items. 3. The worker locks rdev->wiphy 3. cfg80211_dev_free() destroys and and walks rdev state. frees rdev. Cancel sched_scan_res_wk in wiphy_unregister() alongside the other rdev work items. cancel_work_sync() removes a pending result notification and waits for an already running callback, so cfg80211_dev_free() cannot free rdev while this work item is still active. Validation reproduced this kernel report: BUG: KASAN: use-after-free in cfg80211_sched_scan_results_wk+0x4a6/0x530 Workqueue: cfg80211 cfg80211_sched_scan_results_wk [cfg80211] Read of size 8 Call trace: dump_stack_lvl+0x66/0xa0 print_report+0xce/0x630 cfg80211_sched_scan_results_wk+0x4a6/0x530 srso_alias_return_thunk+0x5/0xfbef5 __virt_addr_valid+0x224/0x430 kasan_report+0xac/0xe0 lockdep_hardirqs_on_prepare+0xea/0x1a0 process_one_work+0x8d0/0x18f0 (kernel/workqueue.c:3212) lock_is_held_type+0x8f/0x100 worker_thread+0x5ad/0xfd0 __kthread_parkme+0xc6/0x200 kthread+0x31e/0x410 trace_hardirqs_on+0x1a/0x170 ret_from_fork+0x576/0x810 __switch_to+0x57e/0xe20 __switch_to_asm+0x33/0x70 ret_from_fork_asm+0x1a/0x30
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.
Timeline
- CVE record published.
- CISA published its SSVC assessment (exploitation: none, automatable: no, technical impact: total).
- Record last changed materially (score, affected products, status or references).
References
Other references
- git.kernel.org/stable/c/308ffdf575560d7e7b8b21f1e3ca6276630f73bf
- git.kernel.org/stable/c/3368457b4871ae8f0f88d19c9a3e6270e850ede6
- git.kernel.org/stable/c/9293574ac208d18c11073538851fb69355beb3b5
- git.kernel.org/stable/c/b119c70b24776c8ab2a2c0515397b3b0ad4e66cd
- git.kernel.org/stable/c/b51b42b974461fd0f688baad85f10e2b8ab215c5
- git.kernel.org/stable/c/c0fa1f3a4b021a5c6373169fd6c9bb4261d676a0
- git.kernel.org/stable/c/edf0730be33696a1bd142792830d392129e495cc
Recent Use After Free vulnerabilities
- 7.8 High severity
- 9.8 Critical severity
- 8.8 High severity
- 7.8 High severity
- 7.8 High severity
- 8.8 High severity
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