CVE-2022-49476 | mt76: mt7921: fix kernel crash at mt7921_pci_remove

In the Linux kernel, the following vulnerability has been resolved: mt76: mt7921: fix kernel crash at mt7921_pci_remove The crash log shown it is possible that mt7921_irq_handler is called while devm_free_irq is being handled so mt76_free_device need to be postponed until devm_free_irq is completed to solve the crash we free the mt76 device too early. [ 9299.339655] BUG: kernel NULL pointer dereference, address: 0000000000000008 [ 9299.339705] #PF: supervisor read access in kernel mode [ 9299.339735] #PF: error_code(0x0000) - not-present page [ 9299.339768] PGD 0 P4D 0 [ 9299.339786] Oops: 0000 [#1] SMP PTI [ 9299.339812] CPU: 1 PID: 1624 Comm: prepare-suspend Not tainted 5.15.14-1.fc32.qubes.x86_64 #1 [ 9299.339863] Hardware name: Xen HVM domU, BIOS 4.14.3 01/20/2022 [ 9299.339901] RIP: 0010:mt7921_irq_handler+0x1e/0x70 [mt7921e] [ 9299.340048] RSP: 0018:ffffa81b80c27cb0 EFLAGS: 00010082 [ 9299.340081] RAX: 0000000000000000 RBX: ffff98a4cb752020 RCX: ffffffffa96211c5 [ 9299.340123] RDX: 0000000000000000 RSI: 00000000000d4204 RDI: ffff98a4cb752020 [ 9299.340165] RBP: ffff98a4c28a62a4 R08: ffff98a4c37a96c0 R09: 0000000080150011 [ 9299.340207] R10: 0000000040000000 R11: 0000000000000000 R12: ffff98a4c4eaa080 [ 9299.340249] R13: ffff98a4c28a6360 R14: ffff98a4cb752020 R15: ffff98a4c28a6228 [ 9299.340297] FS: 00007260840d3740(0000) GS:ffff98a4ef700000(0000) knlGS:0000000000000000 [ 9299.340345] CS: 0010 DS: 0000 ES: 0000 CR0: 0000000080050033 [ 9299.340383] CR2: 0000000000000008 CR3: 0000000004c56001 CR4: 0000000000770ee0 [ 9299.340432] PKRU: 55555554 [ 9299.340449] Call Trace: [ 9299.340467] <TASK> [ 9299.340485] __free_irq+0x221/0x350 [ 9299.340527] free_irq+0x30/0x70 [ 9299.340553] devm_free_irq+0x55/0x80 [ 9299.340579] mt7921_pci_remove+0x2f/0x40 [mt7921e] [ 9299.340616] pci_device_remove+0x3b/0xa0 [ 9299.340651] __device_release_driver+0x17a/0x240 [ 9299.340686] device_driver_detach+0x3c/0xa0 [ 9299.340714] unbind_store+0x113/0x130 [ 9299.340740] kernfs_fop_write_iter+0x124/0x1b0 [ 9299.340775] new_sync_write+0x15c/0x1f0 [ 9299.340806] vfs_write+0x1d2/0x270 [ 9299.340831] ksys_write+0x67/0xe0 [ 9299.340857] do_syscall_64+0x3b/0x90 [ 9299.340887] entry_SYSCALL_64_after_hwframe+0x44/0xae

Published: 2025-02-26 Last update: 2025-10-01 Assigner: 416baaa9-dc9f-4396-8d5f-8c081fb06d67 Source: 416baaa9-dc9f-4396-8d5f-8c081fb06d67

Conclusion & alert: CVE-2022-49476 is rated Low Risk (22.7/100): CVSS Medium severity, with low exploitation likelihood (EPSS 0.01%). Mandatory action: Monitor for updates and reassess as exploit intelligence or EPSS changes.

Risk is dynamic; we continuously reassess and refresh what is shown on this page as upstream context changes.

Exploit prediction scoring system (EPSS) score for CVE-2022-49476

EPSS lead: Daily EPSS estimates relative likelihood of exploitation; percentile ranks this CVE among scored vulnerabilities (higher = more severe relative rank).

# Date Old EPSS score New EPSS score Delta (New - Old)
1 2026-05-29 0.07% 0.01% -0.06%
2 2026-04-06 0.04% 0.07% +0.03%
3 2025-02-27 0.04%

Full EPSS history (3 records total)

Common vulnerability scoring system (CVSS) metrics for CVE-2022-49476

CVSS metrics for this CVE.

Base score Version Severity Vector Exploitability Impact Score source
5.5 3.1 MEDIUM
CVSS:3.1/AV:L/AC:L/PR:L/UI:N/S:U/C:N/I:N/A:H Click to expand
Attack vector (AV:L)
They already need access on the box, or another person has to do something wrong; it’s not a remote drive-by.
Attack complexity (AC:L)
Once they can reach the bug, pulling it off is straightforward—no weird race conditions or rare setup.
Privileges required (PR:L)
A normal user session is enough; they don’t have to be admin.
User interaction (UI:N)
Nobody has to click “OK” or open a trap file; it can work without a victim helping.
Scope (S:U)
Damage stays in the same “trust bubble” as the broken component—no big spill into unrelated systems.
Confidentiality (C:N)
Doesn’t really leak secrets in a meaningful way.
Integrity (I:N)
Data isn’t meaningfully altered or forged.
Availability (A:H)
Could take the service down hard or make it unusable for people who depend on it.
1.8 3.6 [email protected]
5.5 3.1 MEDIUM
CVSS:3.1/AV:L/AC:L/PR:L/UI:N/S:U/C:N/I:N/A:H Click to expand
Attack vector (AV:L)
They already need access on the box, or another person has to do something wrong; it’s not a remote drive-by.
Attack complexity (AC:L)
Once they can reach the bug, pulling it off is straightforward—no weird race conditions or rare setup.
Privileges required (PR:L)
A normal user session is enough; they don’t have to be admin.
User interaction (UI:N)
Nobody has to click “OK” or open a trap file; it can work without a victim helping.
Scope (S:U)
Damage stays in the same “trust bubble” as the broken component—no big spill into unrelated systems.
Confidentiality (C:N)
Doesn’t really leak secrets in a meaningful way.
Integrity (I:N)
Data isn’t meaningfully altered or forged.
Availability (A:H)
Could take the service down hard or make it unusable for people who depend on it.
1.8 3.6 134c704f-9b21-4f2e-91b3-4a467353bcc0

Weakness enumeration for CVE-2022-49476

OS Trackers for CVE-2022-49476

vendor priority summary link
debian unimportant CVE-2022-49476 unimportant priority: Debian including 1 source packages (linux), 5 status rows across 5 suites (bookworm, bullseye, forky, sid, trixie): resolved 5. https://security-tracker.debian.org/tracker/CVE-2022-49476
redhat low https://access.redhat.com/security/cve/CVE-2022-49476
suse medium https://www.suse.com/security/cve/CVE-2022-49476/
ubuntu medium CVE-2022-49476 medium priority: Ubuntu including 158 source packages (linux, linux-allwinner-5.19, …), 1551 status rows across 10 suites (bionic, focal, jammy, noble, oracular, plucky, questing, trusty, upstream, xenial): DNE 1145, ignored 146, not-affected 135, released 92, needed 33. https://ubuntu.com/security/CVE-2022-49476

Affected software / configurations for CVE-2022-49476

Vendor Product Version Raw CPE
linux linux_kernel >= 5.12, < 5.17.14 cpe:2.3:o:linux:linux_kernel:*:*:*:*:*:*:*:*
linux linux_kernel >= 5.18, < 5.18.3 cpe:2.3:o:linux:linux_kernel:*:*:*:*:*:*:*:*

References for CVE-2022-49476

cvelogic Threat Intelligence