CVE-2022-49626

What it is

In the Linux kernel, the following vulnerability has been resolved: sfc: fix use after free when disabling sriov Use after free is detected by kfence when disabling sriov. What was read after being freed was vf->pci_dev: it was freed from pci_disable_sriov and later read in efx_ef10_sriov_free_vf_vports, called from efx_ef10_sriov_free_vf_vswitching. Set the pointer to NULL at release time to not trying to read it later. Reproducer and dmesg log (note that kfence doesn't detect it every time): $ echo 1 > /sys/class/net/enp65s0f0np0/device/sriov_numvfs $ echo 0 > /sys/class/net/enp65s0f0np0/device/sriov_numvfs BUG: KFENCE: use-after-free read in efx_ef10_sriov_free_vf_vswitching+0x82/0x170 [sfc] Use-after-free read at 0x00000000ff3c1ba5 (in kfence-#224): efx_ef10_sriov_free_vf_vswitching+0x82/0x170 [sfc] efx_ef10_pci_sriov_disable+0x38/0x70 [sfc] efx_pci_sriov_configure+0x24/0x40 [sfc] sriov_numvfs_store+0xfe/0x140 kernfs_fop_write_iter+0x11c/0x1b0 new_sync_write+0x11f/0x1b0 vfs_write+0x1eb/0x280 ksys_write+0x5f/0xe0 do_syscall_64+0x5c/0x80 entry_SYSCALL_64_after_hwframe+0x44/0xae kfence-#224: 0x00000000edb8ef95-0x00000000671f5ce1, size=2792, cache=kmalloc-4k allocated by task 6771 on cpu 10 at 3137.860196s: pci_alloc_dev+0x21/0x60 pci_iov_add_virtfn+0x2a2/0x320 sriov_enable+0x212/0x3e0 efx_ef10_sriov_configure+0x67/0x80 [sfc] efx_pci_sriov_configure+0x24/0x40 [sfc] sriov_numvfs_store+0xba/0x140 kernfs_fop_write_iter+0x11c/0x1b0 new_sync_write+0x11f/0x1b0 vfs_write+0x1eb/0x280 ksys_write+0x5f/0xe0 do_syscall_64+0x5c/0x80 entry_SYSCALL_64_after_hwframe+0x44/0xae freed by task 6771 on cpu 12 at 3170.991309s: device_release+0x34/0x90 kobject_cleanup+0x3a/0x130 pci_iov_remove_virtfn+0xd9/0x120 sriov_disable+0x30/0xe0 efx_ef10_pci_sriov_disable+0x57/0x70 [sfc] efx_pci_sriov_configure+0x24/0x40 [sfc] sriov_numvfs_store+0xfe/0x140 kernfs_fop_write_iter+0x11c/0x1b0 new_sync_write+0x11f/0x1b0 vfs_write+0x1eb/0x280 ksys_write+0x5f/0xe0 do_syscall_64+0x5c/0x80 entry_SYSCALL_64_after_hwframe+0x44/0xae

At a glance

Exploitability

Can be exploited locally on the machine with a low-privilege account. High risk of data exposure, data tampering, service disruption.

Exploit odds

0.3% chance of exploitation in the next 30 days (EPSS).

Fix

A patch, advisory or fixed version is referenced. Upgrade or apply it.

Timeline

1. 2025-02-26 07:01 UTC PublishedDisclosed publicly on CVE.org and NVD
2. 2026-06-17 05:18 UTC Last updatedMost recent change to the record

Why it ranks here

• Exploited in the wild: no, CISA does not list it.
• Exploit odds: 0.3% in the next 30 days (EPSS).
• Severity: 7.8 HIGH (CVSS).
• Fix: a patch or advisory is linked.

Details

Published

2025-02-26 07:01 UTC

Last modified

2026-06-17 05:18 UTC

Exploit probability

0.3% · EPSS, next 30 days

Weakness

CWE-416 · Use after free

Record status

Analyzed

Affected

• Linux Kernel < 4.9.324
• Linux Kernel < 4.14.289
• Linux Kernel < 4.19.253
• Linux Kernel < 5.4.207
• Linux Kernel < 5.10.132
• Linux Kernel < 5.15.56
• Linux Kernel < 5.18.13
• Linux Kernel 5.19

Attack profile CVSS 3.1 · 7.8

Attack vector

Local

Complexity

Low

Privileges needed

Low

User interaction

None

Scope

Unchanged

Confidentiality

High

Integrity

High

Availability

High

Is it in your code?

Hand this to your coding agent. It searches your project for the affected products and checks versions. Nothing leaves your machine.

Read https://cve-list.com/agent/cve/CVE-2022-49626.md and follow it. Check whether this project is affected by CVE-2022-49626. Read only. Don't change anything and don't upload my code. Tell me yes, no or not sure, with the file as proof.

Copy as ticket · More options · Status badge