Vulnerability in Kernel (CVE-2022-49626)

Summary

Vulnerability in Kernel (CVE-2022-49626). Successful exploitation can lead to full system takeover. Mitigation: upgrade to 4.9.324, 4.14.289, 4.19.253, 5.4.207, 5.10.132, 5.15.56, 5.18.13 or later.

Original description

The description as published by the source.

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…

Source: OSV.dev (Open Source Vulnerabilities) NVD OSV

Auto-generated summary

Assembled by SecPulse from the source data (CVSS, CWE, affected versions) using templates — no AI involved. Check the original description and references below for exact details.

A vulnerability tracked as CVE-2022-49626 has been found in Kernel.
Successful exploitation can lead to full system takeover.
What to do: upgrade Kernel to 4.9.324, 4.14.289, 4.19.253, 5.4.207, 5.10.132, 5.15.56, 5.18.13 or later.
If unsure, ask your IT team or search "Kernel CVE-2022-49626" on the vendor's site.

CVE-2022-49626 (Kernel)
Attack vector: local / no user interaction
Patched: 4.9.324, 4.14.289, 4.19.253, 5.4.207, 5.10.132, 5.15.56, 5.18.13 — apply immediately
Plan: 1) Audit SBOM/dependencies, 2) Stage→prod upgrade, 3) Add WAF/proxy monitoring on affected endpoints, 4) Hunt IOCs in logs.
Refs: see the GHSA / vendor advisory / patched release linked on this page.

❓ What is the problem

A vulnerability (unclassified) exists in Kernel.

📍 Affected scope

Check the vendor advisory for the affected versions of Kernel.

🔥 Severity

Severity: ?. Successful exploitation can lead to full system takeover.

🔧 How to fix

Update to 4.9.324, 4.14.289, 4.19.253, 5.4.207, 5.10.132, 5.15.56, 5.18.13.

🛡️ Workaround

Until the patch is applied: disable the affected feature, apply WAF rules, or restrict access via network ACLs.

🔍 Detection

Search webserver/proxy logs for unusual request patterns matching this CVE's known IOCs. Run grep -r 'Kernel' . against your dependency files (package-lock.json, requirements.txt, go.sum) to find affected services.

Response actions

Concrete steps and command examples for SOC/SRE teams to execute in order

1
Identify exposure identify
```
grep -r 'Kernel' . | grep -v node_modules
```
リポジトリと本番環境の依存ファイル (package-lock.json / requirements.txt / go.sum / Gemfile.lock 等) で Kernel を grep し、稼働しているサービス・バージョンを把握する。
2
Apply patch patch
```
Upgrade Kernel to 4.9.324, 4.14.289, 4.19.253, 5.4.207, 5.10.132, 5.15.56, 5.18.13
```
ステージング環境で 4.9.324, 4.14.289, 4.19.253, 5.4.207, 5.10.132, 5.15.56, 5.18.13 に上げて回帰テスト → 本番反映。回帰テストはアプリの主要ハッピーパスを含めること。
3
Post-deployment verification verify
```
Confirm patched version is live in production
```
パッチ適用後、ステージングで PoC または同等の悪用パターンを再現して脆弱性が閉じたことを確認。本番ではアクセスログ・WAF でアラート再発が無いか継続監視。

Affected packages

Linux Kernel

[{"type":"ECOSYSTEM","events":[{"introduced":"4.2.0"},{"fixed":"4.9.324"}]},{"type":"ECOSYSTEM","events":[{"introduced":"4.10.0"},{"fixed":"4.14.289"}]},{"type":"ECOSYSTEM","events":[{"introduced":"4.15.0"},{"fixed":"4.19.253"}]},{"type":"ECOSYSTEM","events":[{"introduced":"4.20.0"},{"fixed":"5.4.207"}]},{"type":"ECOSYSTEM","events":[{"introduced":"5.5.0"},{"fixed":"5.10.132"}]},{"type":"ECOSYSTEM","events":[{"introduced":"5.11.0"},{"fixed":"5.15.56"}]},{"type":"ECOSYSTEM","events":[{"introduced":"5.16.0"},{"fixed":"5.18.13"}]}]

Fix status by distribution

Fixed packages published by each distribution for this CVE

Debian DEBIAN-CVE-2022-49626 linux Fixed in: 5.10.136-1
Ubuntu UBUNTU-CVE-2022-49626 linux-azure Fixed in: 4.15.0-1153.168~14.04.1