In the Linux kernel, the following vulnerability has been resolved:
Bluetooth: hci_sysfs: Fix attempting to call device_add multiple times
device_add shall not be called multiple times as stated in its
documentation:
'Do not call this routine or device_register() more than once for
any device structure'
Syzkaller reports a bug as follows [1]:
------------[ cut here ]------------
kernel BUG at lib/list_debug.c:33!
invalid opcode: 0000 [#1] PREEMPT SMP KASAN
[...]
Call Trace:
__list_add include/linux/list.h:69 [inline]
list_add_tail include/linux/list.h:102 [inline]
kobj_kset_join lib/kobject.c:164 [inline]
kobject_add_internal+0x18f/0x8f0 lib/kobject.c:214
kobject_add_varg lib/kobject.c:358 [inline]
kobject_add+0x150/0x1c0 lib/kobject.c:410
device_add+0x368/0x1e90 drivers/base/core.c:3452
hci_conn_add_sysfs+0x9b/0x1b0 net/bluetooth/hci_sysfs.c:53
hci_le_cis_estabilished_evt+0x57c/0xae0 net/bluetooth/hci_event.c:6799
hci_le_meta_evt+0x2b8/0x510 net/bluetooth/hci_event.c:7110
hci_event_func net/bluetooth/hci_event.c:7440 [inline]
hci_event_packet+0x63d/0xfd0 net/bluetooth/hci_event.c:7495
hci_rx_work+0xae7/0x1230 net/bluetooth/hci_core.c:4007
process_one_work+0x991/0x1610 kernel/workqueue.c:2289
worker_thread+0x665/0x1080 kernel/workqueue.c:2436
kthread+0x2e4/0x3a0 kernel/kthread.c:376
ret_from_fork+0x1f/0x30 arch/x86/entry/entry_64.S:306
What the EG score is made of (scorer v4.0: the three questions the 0–10 score mixes, published apart · methodology)
The EG score (7.8): severity, escalated by confirmed exploitation. This CVE's 7.8 is its impact severity (EG Severity), not escalated.
- EG Severity
- 7.8 HIGHCVSS-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 2026-10-28). 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