In the Linux kernel, the following vulnerability has been resolved:
wifi: rtw89: Correct data type for scan index to avoid infinite loop
A kernel soft lockup was observed during Wi-Fi scanning on the 6GHz band.
The CPU becomes stuck in rtw89_hw_scan_add_chan_ax for over 20 seconds,
leading to a system panic.
RIP points to 0f b6 c3 (movzbl %bl, %eax), which zero-extends
the low 8 bits of RBX into RAX.
RBX (the counter i) has reached a huge value: 0x137466a1.
watchdog: BUG: soft lockup - CPU#2 stuck for 26s! [kworker/u16:4:6124]
Workqueue: events_unbound cfg80211_wiphy_work [cfg80211]
RIP: 0010:rtw89_hw_scan_add_chan_ax+0xb3/0x6e0 [rtw89_core]
Code: a0 48 89 45 a8 44 89 6d 9c 44 89 75 98 eb 29 66 66 2e 0f 1f
84 00 00 00 00 00 66 66 2e 0f 1f 84 00 00 00 00 00 66 90 83 c3 01
<0f> b6 c3 41 3b 44 24 74 0f 83 0b 02 00 00 0f b6 c3 48 8d 14 80 49
RSP: 0018:ffffcb48cbaa39f8 EFLAGS: 00000202
RAX: 0000000000000005 RBX: 00000000137466a1 RCX: 0000000000000000
RDX: ffff89ffc9d851a8 RSI: 0000000000004f0d RDI: 0000000096af0130
RBP: ffffcb48cbaa3a60 R08: 0000000000000000 R09: ffff8a00b7502080
R10: ffff8a00b75ff600 R11: 0000000000000000 R12: ffff89ffc7553870
R13: ffff8a00b7ac8f19 R14: ffff8a00b75020d8 R15: ffff89ffc3d54d80
FS: 0000000000000000(0000) GS:ffff8a014f962000(0000)
knlGS:0000000000000000
CS: 0010 DS: 0000 ES: 0000 CR0: 0000000080050033
CR2: 00007558d7f9f4c4 CR3: 0000000178040001 CR4: 00000000001706f0
Call Trace:
rtw89_hw_scan_prep_chan_list_ax+0x8a/0x400 [rtw89_core]
rtw89_hw_scan_start+0x546/0x8a0 [rtw89_core]
? rtw89_fw_h2c_default_cmac_tbl+0x13c/0x1f0 [rtw89_core]
rtw89_ops_hw_scan+0xae/0x120 [rtw89_core]
drv_hw_scan+0xbb/0x180 [mac80211]
__ieee80211_start_scan+0x2fc/0x750 [mac80211]
ieee80211_request_scan+0xe/0x20 [mac80211]
ieee80211_scan+0x123/0x190 [mac80211]
rdev_scan+0x40/0x110 [cfg80211]
cfg80211_scan_6ghz+0x5a1/0xa30 [cfg80211]
By objdump with source:
for (i = 0; i < req->n_6ghz_params; i++) {
5fbc0: 83 c3 01 add $0x1,%ebx --> i++
5fbc3: 0f b6 c3 movzbl %bl,%eax --> get counter
fbc6: 41 3b 44 24 74 cmp 0x74(%r12),%eax
* RBX: 00000000137466a1 -> %bl = a1 -> EAX = 000000a1 (161)
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
- 0.4% within 30 daysSource: FIRST EPSS (model v2026.06.15, score date 2026-10-31). 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