CVE-2022-48876

MEDIUM EPSS 10.9%

Published Aug 21, 20241y ago · Modified Jun 17, 20261w ago

5.5 CVSS 3.1

Medium

Published Aug 21, 2024 1y ago

Last Modified Jun 17, 2026 1w ago

Description

In the Linux kernel, the following vulnerability has been resolved: wifi: mac80211: fix initialization of rx->link and rx->link_sta There are some codepaths that do not initialize rx->link_sta properly. This causes a crash in places which assume that rx->link_sta is valid if rx->sta is valid. One known instance is triggered by __ieee80211_rx_h_amsdu being called from fast-rx. It results in a crash like this one: BUG: kernel NULL pointer dereference, address: 00000000000000a8 #PF: supervisor write access in kernel mode #PF: error_code(0x0002) - not-present page PGD 0 P4D 0 Oops: 0002 [#1] PREEMPT SMP PTI CPU: 1 PID: 506 Comm: mt76-usb-rx phy Tainted: G E 6.1.0-debian64x+1.7 #3 Hardware name: ZOTAC ZBOX-ID92/ZBOX-IQ01/ZBOX-ID92/ZBOX-IQ01, BIOS B220P007 05/21/2014 RIP: 0010:ieee80211_deliver_skb+0x62/0x1f0 [mac80211] Code: 00 48 89 04 24 e8 9e a7 c3 df 89 c0 48 03 1c c5 a0 ea 39 a1 4c 01 6b 08 48 ff 03 48 83 7d 28 00 74 11 48 8b 45 30 48 63 55 44 <48> 83 84 d0 a8 00 00 00 01 41 8b 86 c0 11 00 00 8d 50 fd 83 fa 01 RSP: 0018:ffff999040803b10 EFLAGS: 00010286 RAX: 0000000000000000 RBX: ffffb9903f496480 RCX: 0000000000000000 RDX: 0000000000000000 RSI: 0000000000000000 RDI: 0000000000000000 RBP: ffff999040803ce0 R08: 0000000000000000 R09: 0000000000000000 R10: 0000000000000000 R11: 0000000000000000 R12: ffff8d21828ac900 R13: 000000000000004a R14: ffff8d2198ed89c0 R15: ffff8d2198ed8000 FS: 0000000000000000(0000) GS:ffff8d24afe80000(0000) knlGS:0000000000000000 CS: 0010 DS: 0000 ES: 0000 CR0: 0000000080050033 CR2: 00000000000000a8 CR3: 0000000429810002 CR4: 00000000001706e0 Call Trace: <TASK> __ieee80211_rx_h_amsdu+0x1b5/0x240 [mac80211] ? ieee80211_prepare_and_rx_handle+0xcdd/0x1320 [mac80211] ? __local_bh_enable_ip+0x3b/0xa0 ieee80211_prepare_and_rx_handle+0xcdd/0x1320 [mac80211] ? prepare_transfer+0x109/0x1a0 [xhci_hcd] ieee80211_rx_list+0xa80/0xda0 [mac80211] mt76_rx_complete+0x207/0x2e0 [mt76] mt76_rx_poll_complete+0x357/0x5a0 [mt76] mt76u_rx_worker+0x4f5/0x600 [mt76_usb] ? mt76_get_min_avg_rssi+0x140/0x140 [mt76] __mt76_worker_fn+0x50/0x80 [mt76] kthread+0xed/0x120 ? kthread_complete_and_exit+0x20/0x20 ret_from_fork+0x22/0x30 Since the initialization of rx->link and rx->link_sta is rather convoluted and duplicated in many places, clean it up by using a helper function to set it. [remove unnecessary rx->sta->sta.mlo check]

CVSS Details

Base Score

5.5

Exploitability

1.8

Impact

3.6

Vector string

CVSS:3.1/AV:L/AC:L/PR:L/UI:N/S:U/C:N/I:N/A:H

Attack Vector Local

Attack Complexity Low

Privileges Required Low

User Interaction None

Scope Unchanged

Confidentiality None

Integrity None

Availability High

Threat Intelligence

EPSS Exploit Probability

10.9% percentile

Exploit & Patch Status

No Known Exploit

Patch Available

Weaknesses 1

CWE-476 NULL Pointer Dereference Memory Safety

Affected Products 1

Vendor	Product	Version	Range
linux	linux_kernel	*	≥6.1 – <6.1.8

References 2

git.kernel.org https://git.kernel.org/stable/c/a57c981d9f24d2bd89eaa76dc477e8ca252e22e8

Patch
git.kernel.org https://git.kernel.org/stable/c/e66b7920aa5ac5b1a1997a454004ba9246a3c005

Patch

Remediation

git.kernel.org https://git.kernel.org/stable/c/a57c981d9f24d2bd89eaa76dc477e8ca252e22e8

Patch
git.kernel.org https://git.kernel.org/stable/c/e66b7920aa5ac5b1a1997a454004ba9246a3c005

Patch