In the Linux kernel, the following vulnerability has been resolved:
leds: led-class: Only Add LED to leds_list when it is fully ready
Before this change the LED was added to leds_list before led_init_core()
gets called adding it the list before led_classdev.set_brightness_work gets
initialized.
This leaves a window where led_trigger_register() of a LED's default
trigger will call led_trigger_set() which calls led_set_brightness()
which in turn will end up queueing the *uninitialized*
led_classdev.set_brightness_work.
This race gets hit by the lenovo-thinkpad-t14s EC driver which registers
2 LEDs with a default trigger provided by snd_ctl_led.ko in quick
succession. The first led_classdev_register() causes an async modprobe of
snd_ctl_led to run and that async modprobe manages to exactly hit
the window where the second LED is on the leds_list without led_init_core()
being called for it, resulting in:
------------[ cut here ]------------
WARNING: CPU: 11 PID: 5608 at kernel/workqueue.c:4234 __flush_work+0x344/0x390
Hardware name: LENOVO 21N2S01F0B/21N2S01F0B, BIOS N42ET93W (2.23 ) 09/01/2025
...
Call trace:
__flush_work+0x344/0x390 (P)
flush_work+0x2c/0x50
led_trigger_set+0x1c8/0x340
led_trigger_register+0x17c/0x1c0
led_trigger_register_simple+0x84/0xe8
snd_ctl_led_init+0x40/0xf88 [snd_ctl_led]
do_one_initcall+0x5c/0x318
do_init_module+0x9c/0x2b8
load_module+0x7e0/0x998
Close the race window by moving the adding of the LED to leds_list to
after the led_init_core() call.
What the EG score is made of (scorer v4.0: the three questions the 0–10 score mixes, published apart · methodology)
The EG score (4.7): severity, escalated by confirmed exploitation. This CVE's 4.7 is its impact severity (EG Severity), not escalated.
- EG Severity
- 4.7 MEDIUMCVSS-B, impact only: no KEV listing, EPSS or EG-KEV tier raises it.GitHub Security Advisory CVSS
- EG Likelihood
- 0.1% within 30 daysSource: FIRST EPSS. 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 every mission impact level.CISA BOD 26-04: 60 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 every mission impact level.
A fix is available. Apply it within your standard update timelines.
Exploitation none (CISA Vulnrichment) · Automatable no (CISA Vulnrichment) · Technical impact partial (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)60 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 partial (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