CVE-2026-74411

Received Received - Intake

Soft lockup in rtw89 Wi-Fi driver during 6GHz scan

Publication date: 2026-08-15

Last updated on: 2026-08-17

Assigner: kernel.org

Description

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: <TASK> 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)

CVSS Scores

EPSS Scores

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Meta Information

Published

2026-08-15

Last Modified

2026-08-17

Generated

2026-09-04

AI Q&A

2026-08-15

EPSS Evaluated

2026-09-03

NVD

CVE-2026-74411

EUVD

EUVD-2026-59558

Affected Vendors & Products

Currently, no data is known.

Helpful Resources

Exploitability

CWE

KEV

CWE ID	Description
CWE-UNKNOWN

Attack-Flow Graph

Executive Summary

This is a Linux kernel vulnerability in the rtw89 Wi-Fi driver where a data type error causes an infinite loop during Wi-Fi scanning on the 6GHz band. The loop counter becomes excessively large, leading to a CPU soft lockup and system panic.

Detection Guidance

This vulnerability causes a kernel soft lockup during Wi-Fi scanning on the 6GHz band, leading to a system panic. Check kernel logs for messages like 'soft lockup - CPU#X stuck for Ys!' or 'rtw89_hw_scan_add_chan_ax' errors. Use 'dmesg | grep -i lockup' or 'journalctl -k | grep -i lockup' to detect it.

Impact Analysis

This vulnerability can cause system freezes or crashes during Wi-Fi operations, potentially leading to denial of service. Users may experience unresponsive systems or unexpected reboots when scanning Wi-Fi networks.

Compliance Impact

This vulnerability causes a kernel soft lockup during Wi-Fi scanning, leading to system instability and potential crashes. Such instability could disrupt critical services, potentially causing data processing interruptions that may violate compliance requirements for availability in standards like GDPR and HIPAA.

Mitigation Strategies

Apply the Linux kernel patch that resolves this issue. Update your kernel to a version containing the fix for the rtw89 driver. If immediate patching is not possible, disable Wi-Fi scanning on the 6GHz band or disable the affected rtw89 driver module.

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