In the Linux kernel, the following vulnerability has been resolved:
wifi: cfg80211: Add missing lock in cfg80211_check_and_end_cac()
Callers of wdev_chandef() must hold the wiphy mutex.
But the worker cfg80211_propagate_cac_done_wk() never takes the lock.
Which triggers the warning below with the mesh_peer_connected_dfs
test from hostapd and not (yet) released mac80211 code changes:
WARNING: CPU: 0 PID: 495 at net/wireless/chan.c:1552 wdev_chandef+0x60/0x165
Modules linked in:
CPU: 0 UID: 0 PID: 495 Comm: kworker/u4:2 Not tainted 6.14.0-rc5-wt-g03960e6f9d47 #33 13c287eeabfe1efea01c0bcc863723ab082e17cf
Workqueue: cfg80211 cfg80211_propagate_cac_done_wk
Stack:
00000000 00000001 ffffff00 6093267c
00000000 6002ec30 6d577c50 60037608
00000000 67e8d108 6063717b 00000000
Call Trace:
[<6002ec30>] ? _printk+0x0/0x98
[<6003c2b3>] show_stack+0x10e/0x11a
[<6002ec30>] ? _printk+0x0/0x98
[<60037608>] dump_stack_lvl+0x71/0xb8
[<6063717b>] ? wdev_chandef+0x60/0x165
[<6003766d>] dump_stack+0x1e/0x20
[<6005d1b7>] __warn+0x101/0x20f
[<6005d3a8>] warn_slowpath_fmt+0xe3/0x15d
[<600b0c5c>] ? mark_lock.part.0+0x0/0x4ec
[<60751191>] ? __this_cpu_preempt_check+0x0/0x16
[<600b11a2>] ? mark_held_locks+0x5a/0x6e
[<6005d2c5>] ? warn_slowpath_fmt+0x0/0x15d
[<60052e53>] ? unblock_signals+0x3a/0xe7
[<60052f2d>] ? um_set_signals+0x2d/0x43
[<60751191>] ? __this_cpu_preempt_check+0x0/0x16
[<607508b2>] ? lock_is_held_type+0x207/0x21f
[<6063717b>] wdev_chandef+0x60/0x165
[<605f89b4>] regulatory_propagate_dfs_state+0x247/0x43f
[<60052f00>] ? um_set_signals+0x0/0x43
[<605e6bfd>] cfg80211_propagate_cac_done_wk+0x3a/0x4a
[<6007e460>] process_scheduled_works+0x3bc/0x60e
[<6007d0ec>] ? move_linked_works+0x4d/0x81
[<6007d120>] ? assign_work+0x0/0xaa
[<6007f81f>] worker_thread+0x220/0x2dc
[<600786ef>] ? set_pf_worker+0x0/0x57
[<60087c96>] ? to_kthread+0x0/0x43
[<6008ab3c>] kthread+0x2d3/0x2e2
[<6007f5ff>] ? worker_thread+0x0/0x2dc
[<6006c05b>] ? calculate_sigpending+0x0/0x56
[<6003b37d>] new_thread_handler+0x4a/0x64
irq event stamp: 614611
hardirqs last enabled at (614621): [<00000000600bc96b>] __up_console_sem+0x82/0xaf
hardirqs last disabled at (614630): [<00000000600bc92c>] __up_console_sem+0x43/0xaf
softirqs last enabled at (614268): [<00000000606c55c6>] __ieee80211_wake_queue+0x933/0x985
softirqs last disabled at (614266): [<00000000606c52d6>] __ieee80211_wake_queue+0x643/0x985
What the EG score is made of (scorer v4.0: the three questions the 0–10 score mixes, published apart · methodology)
The EG score (5.5): severity, escalated by confirmed exploitation. This CVE's 5.5 is its impact severity (EG Severity), not escalated.
- EG Severity
- 5.5 MEDIUMCVSS-B, impact only: no KEV listing, EPSS or EG-KEV tier raises it.GitHub Security Advisory CVSS
- EG Likelihood
- 0.2% within 30 daysSource: FIRST EPSS (model v2026.06.15, score date 2026-10-24). FIRST's exploitation probability, not an EchelonGraph model.
- Confirmed exploitation
- None on record (CISA KEV, EG-KEV Tier 1)Reported apart from the likelihood: an observed fact, not a probability.
- EG Priority
- SSVC Track at medium mission impactTrack at low or medium mission impact; Track* at high (mission-essential systems).CISA BOD 26-04: 14 days if the affected system is publicly exposed; Fix on system upgrade if it is not.Each input and its source, and whom BOD 26-04 binds: the SSVC and BOD 26-04 blocks below.
SSVC (CISA's decision table, applied by EchelonGraph)Track at low or medium mission impact; Track* at high (mission-essential systems).
A fix is available. Apply it within your standard update timelines.
Exploitation none (CISA Vulnrichment) · Automatable no (CISA Vulnrichment) · Technical impact total (CISA Vulnrichment). All three are CISA's SSVC values (Vulnrichment). EchelonGraph applied CISA's decision table to them; CISA publishes SSVC inputs and the table, not a decision for each CVE. Mission impact is CISA's Mission & Well-being decision point, and only you can judge it. CISA's table makes it high when Mission Prevalence is Essential — the vulnerable component "directly provides capabilities that constitute at least one MEF for at least one entity" (MEF: mission essential function) — or when Public Well-Being Impact is Irreversible: "multiple fatalities are likely", the cyber-physical system "is likely lost or destroyed", "extreme or serious externalities" are imposed on other parties, or social systems such as elections or the financial grid "are destabilized and potentially collapse". CISA's decision table
BOD 26-04 (CISA's remediation timeline, Table 1)14 days if the affected system is publicly exposed; Fix on system upgrade if it is not.
The score's inputs: In CISA KEV no (CISA's KEV catalog) · Automatable no (CISA Vulnrichment) · Technical impact total (CISA Vulnrichment). Whether your system is publicly exposed is yours to answer. BOD 26-04 binds US Federal Civilian Executive Branch agencies; for anyone else it is CISA's published timeline, a reference rather than an obligation. The directive · how EchelonGraph applies it