CVE-2022-50178 wifi: rtw89: 8852a: rfk: fix div 0 exception

Medium 5.5 Published 18 Jun 2025 Updated 11 May 2026

A divide-by-zero error in the rtw89 WiFi driver causes a kernel crash during RF calibration, leading to a denial of service.

Exploited in the wild: Not known
Login needed: Any signed-in user
Attackable: Local or same network only
Victim action needed: Not needed
Fix: Available

What is CVE-2022-50178?

CVE-2022-50178 is a medium-severity denial of service vulnerability in Linux kernel, published on 18 Jun 2025. It can only be exploited from the same machine or local network, with no action from the victim.

Official description

In the Linux kernel, the following vulnerability has been resolved:

wifi: rtw89: 8852a: rfk: fix div 0 exception

The DPK is a kind of RF calibration whose algorithm is to fine tune parameters and calibrate, and check the result. If the result isn't good enough, it could adjust parameters and try again.

This issue is to read and show the result, but it could be a negative calibration result that causes divisor 0 and core dump. So, fix it by phy_div() that does division only if divisor isn't zero; otherwise, zero is adopted.

divide error: 0000 [#1] PREEMPT SMP NOPTI CPU: 1 PID: 728 Comm: wpa_supplicant Not tainted 5.10.114-16019-g462a1661811a #1 <HASH:d024 28> RIP: 0010:rtw8852a_dpk+0x14ae/0x288f [rtw89_core] RSP: 0018:ffffa9bb412a7520 EFLAGS: 00010246 RAX: 0000000000000000 RBX: 0000000000000000 RCX: 0000000000000000 RDX: 0000000000000000 RSI: 00000000000180fc RDI: ffffa141d01023c0 RBP: ffffa9bb412a76a0 R08: 0000000000001319 R09: 00000000ffffff92 R10: ffffffffc0292de3 R11: ffffffffc00d2f51 R12: 0000000000000000 R13: ffffa141d01023c0 R14: ffffffffc0290250 R15: ffffa141d0102638 FS: 00007fa99f5c2740(0000) GS:ffffa142e5e80000(0000) knlGS:0000000000000000 CS: 0010 DS: 0000 ES: 0000 CR0: 0000000080050033 CR2: 0000000013e8e010 CR3: 0000000110d2c000 CR4: 0000000000750ee0 PKRU: 55555554 Call Trace: rtw89_core_sta_add+0x95/0x9c [rtw89_core <HASH:d239 29>] rtw89_ops_sta_state+0x5d/0x108 [rtw89_core <HASH:d239 29>] drv_sta_state+0x115/0x66f [mac80211 <HASH:81fe 30>] sta_info_insert_rcu+0x45c/0x713 [mac80211 <HASH:81fe 30>] sta_info_insert+0xf/0x1b [mac80211 <HASH:81fe 30>] ieee80211_prep_connection+0x9d6/0xb0c [mac80211 <HASH:81fe 30>] ieee80211_mgd_auth+0x2aa/0x352 [mac80211 <HASH:81fe 30>] cfg80211_mlme_auth+0x160/0x1f6 [cfg80211 <HASH:00cd 31>] nl80211_authenticate+0x2e5/0x306 [cfg80211 <HASH:00cd 31>] genl_rcv_msg+0x371/0x3a1 ? nl80211_stop_sched_scan+0xe5/0xe5 [cfg80211 <HASH:00cd 31>] ? genl_rcv+0x36/0x36 netlink_rcv_skb+0x8a/0xf9 genl_rcv+0x28/0x36 netlink_unicast+0x27b/0x3a0 netlink_sendmsg+0x2aa/0x469 sock_sendmsg_nosec+0x49/0x4d ____sys_sendmsg+0xe5/0x213 __sys_sendmsg+0xec/0x157 ? syscall_enter_from_user_mode+0xd7/0x116 do_syscall_64+0x43/0x55 entry_SYSCALL_64_after_hwframe+0x44/0xa9 RIP: 0033:0x7fa99f6e689b

Weakness: CWE-369

Which versions are affected by CVE-2022-50178?

It affects 1 product.

Products include Linux kernel.

How do I fix CVE-2022-50178?

Apply the vendor's patch.

Upgrade, then put limits on request size, rate and nesting depth so one client cannot exhaust the service. More about Denial of service.

Is CVE-2022-50178 being exploited?

There is no known exploitation of CVE-2022-50178 in the wild and no public exploit code.

All Linux kernel vulnerabilities

Sources

Also known as DEBIAN-CVE-2022-50178, GHSA-3wj6-j9c9-3mmg, ROOT-OS-UBUNTU-2204-CVE-2022-50178, UBUNTU-CVE-2022-50178.