CVE-2022-49626

HIGH EPSS 16.6%
Published Feb 26, 20251y ago · Modified Jun 17, 20261w ago
7.8 CVSS 3.1
High
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Published Feb 26, 2025 1y ago
Last Modified Jun 17, 2026 1w ago

Description

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

CVSS Details

Base Score
7.8
Exploitability
1.8
Impact
5.9
Vector string
CVSS:3.1/AV:L/AC:L/PR:L/UI:N/S:U/C:H/I:H/A:H
Attack Vector Local
Attack Complexity Low
Privileges Required Low
User Interaction None
Scope Unchanged
Confidentiality High
Integrity High
Availability High

Threat Intelligence

EPSS Exploit Probability
16.6% percentile
Exploit & Patch Status
No Known Exploit
Patch Available

Weaknesses 1

CWE-416 Use After Free Memory Safety

Affected Products 13

VendorProductVersionRange
linuxlinux_kernel*≥4.2  –  <4.9.324
linuxlinux_kernel*≥4.10  –  <4.14.289
linuxlinux_kernel*≥4.15  –  <4.19.253
linuxlinux_kernel*≥4.20  –  <5.4.207
linuxlinux_kernel*≥5.5  –  <5.10.132
linuxlinux_kernel*≥5.11  –  <5.15.56
linuxlinux_kernel*≥5.16  –  <5.18.13
linuxlinux_kernel5.19any
linuxlinux_kernel5.19any
linuxlinux_kernel5.19any
linuxlinux_kernel5.19any
linuxlinux_kernel5.19any
linuxlinux_kernel5.19any

References 8

  • git.kernel.org https://git.kernel.org/stable/c/3199e34912d84cdfb8a93a984c5ae5c73fb13e84
    Patch
  • git.kernel.org https://git.kernel.org/stable/c/58d93e9d160c0de6d867c7eb4c2206671a351eb1
    Patch
  • git.kernel.org https://git.kernel.org/stable/c/9c854ae512b89229aeee93849e9bd4c115b37909
    Patch
  • git.kernel.org https://git.kernel.org/stable/c/bcad880865bfb421885364b1f0c7351280fe2b97
    Patch
  • git.kernel.org https://git.kernel.org/stable/c/c2240500817b3b4b996cdf2a461a3a5679f49b94
    Patch
  • git.kernel.org https://git.kernel.org/stable/c/c9e75bb22a26e391f189f5a5133dd63dcb57fdaa
    Patch
  • git.kernel.org https://git.kernel.org/stable/c/e435c4aeeaa073091f7f3b7735af2ef5c97d63f2
    Patch
  • git.kernel.org https://git.kernel.org/stable/c/ebe41da5d47ac0fff877e57bd14c54dccf168827
    Patch

Remediation

  • git.kernel.org https://git.kernel.org/stable/c/3199e34912d84cdfb8a93a984c5ae5c73fb13e84
    Patch
  • git.kernel.org https://git.kernel.org/stable/c/58d93e9d160c0de6d867c7eb4c2206671a351eb1
    Patch
  • git.kernel.org https://git.kernel.org/stable/c/9c854ae512b89229aeee93849e9bd4c115b37909
    Patch
  • git.kernel.org https://git.kernel.org/stable/c/bcad880865bfb421885364b1f0c7351280fe2b97
    Patch
  • git.kernel.org https://git.kernel.org/stable/c/c2240500817b3b4b996cdf2a461a3a5679f49b94
    Patch
  • git.kernel.org https://git.kernel.org/stable/c/c9e75bb22a26e391f189f5a5133dd63dcb57fdaa
    Patch
  • git.kernel.org https://git.kernel.org/stable/c/e435c4aeeaa073091f7f3b7735af2ef5c97d63f2
    Patch
  • git.kernel.org https://git.kernel.org/stable/c/ebe41da5d47ac0fff877e57bd14c54dccf168827
    Patch