In the Linux kernel, the following vulnerability has been resolved:
wifi: rtw88: use work to update rate to avoid RCU warning
The ieee80211_ops::sta_rc_update must be atomic, because
ieee80211_chan_bw_change() holds rcu_read lock while calling
drv_sta_rc_update(), so create a work to do original things.
Voluntary context switch within RCU read-side critical section!
WARNING: CPU: 0 PID: 4621 at kernel/rcu/tree_plugin.h:318
rcu_note_context_switch+0x571/0x5d0
CPU: 0 PID: 4621 Comm: kworker/u16:2 Tainted: G W OE
Workqueue: phy3 ieee80211_chswitch_work [mac80211]
RIP: 0010:rcu_note_context_switch+0x571/0x5d0
Call Trace:
__schedule+0xb0/0x1460
? __mod_timer+0x116/0x360
schedule+0x5a/0xc0
schedule_timeout+0x87/0x150
? trace_raw_output_tick_stop+0x60/0x60
wait_for_completion_timeout+0x7b/0x140
usb_start_wait_urb+0x82/0x160 [usbcore
usb_control_msg+0xe3/0x140 [usbcore
rtw_usb_read+0x88/0xe0 [rtw_usb
rtw_usb_read8+0xf/0x10 [rtw_usb
rtw_fw_send_h2c_command+0xa0/0x170 [rtw_core
rtw_fw_send_ra_info+0xc9/0xf0 [rtw_core
drv_sta_rc_update+0x7c/0x160 [mac80211
ieee80211_chan_bw_change+0xfb/0x110 [mac80211
ieee80211_change_chanctx+0x38/0x130 [mac80211
ieee80211_vif_use_reserved_switch+0x34e/0x900 [mac80211
ieee80211_link_use_reserved_context+0x88/0xe0 [mac80211
ieee80211_chswitch_work+0x95/0x170 [mac80211
process_one_work+0x201/0x410
worker_thread+0x4a/0x3b0
? process_one_work+0x410/0x410
kthread+0xe1/0x110
? kthread_complete_and_exit+0x20/0x20
ret_from_fork+0x1f/0x30
What the EG score is made of (scorer v4.0: the three questions the 0–10 score mixes, published apart · methodology)
The EG score (8.8): severity, escalated by confirmed exploitation. This CVE's 8.8 is its impact severity (EG Severity), not escalated.
- EG Severity
- 8.8 HIGHCVSS-B, impact only: no KEV listing, EPSS or EG-KEV tier raises it.GitHub Security Advisory CVSS
- EG Likelihood
- 0.3% within 30 daysSource: FIRST EPSS (model v2026.06.15, score date 2026-10-30). 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