Vulnerability in Linux kernel (CVE-2021-47438)
Summary
Vulnerability in Linux kernel (CVE-2021-47438). Confidential information can be exposed externally.
Original description
The description as published by the source.
In the Linux kernel, the following vulnerability has been resolved:
net/mlx5e: Fix memory leak in mlx5_core_destroy_cq() error path
Prior to this patch in case mlx5_core_destroy_cq() failed it returns
without completing all destroy operations and that leads to memory leak.
Instead, complete the destroy flow before return error.
Also move mlx5_debug_cq_remove() to the beginning of mlx5_core_destroy_cq()
to be symmetrical with mlx5_core_create_cq().
kmemleak complains on:
unreferenced object 0xc000000038625100 (size 64):
comm "ethtool", pid 28301, jiffies 4298062946 (age 785.380s)
hex dump (first 32 bytes):
60 01 48 94 00 00 00 c0 b8 05 34 c3 00 00 00 c0 `.H.......4.....
02 00 00 00 00 00 00 00 00 db 7d c1 00 00 00 c0 ..........}.....
backtrace:
[<000000009e8643cb>] add_res_tree+0xd0/0x270 [mlx5_core]
[<00000000e7cb8e6c>] mlx5_debug_cq_add+0x5c/0xc0 [mlx5_core]
[<000000002a12918f>] mlx5_core_create_cq+0x1d0/0x2d0 [mlx5_core]
[<00000000cef0a696>] mlx5e_create_cq+0x210/0x3f0 [mlx5_core]
[<000000009c642c26>] mlx5e_open_cq+0xb4/0x130 [mlx5_core]
[<0000000058dfa578>] mlx5e_ptp_open+0x7f4/0xe10 [mlx5_core]
[<0000000081839561>] mlx5e_open_channels+0x9cc/0x13e0 [mlx5_core]
[<0000000009cf05d4>] mlx5e_switch_priv_channels+0xa4/0x230
[mlx5_core]
[<0000000042bbedd8>] mlx5e_safe_switch_params+0x14c/0x300
[mlx5_core]
[<0000000004bc9db8>] set_pflag_tx_port_ts+0x9c/0x160 [mlx5_core]
[<00000000a0553443>] mlx5e_set_priv_flags+0xd0/…
Source: NIST National Vulnerability Database NVD
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-2021-47438 has been found in Linux kernel.
Confidential information can be exposed externally. CVSS score: 7.1/10.
What to do: apply the vendor's official patched release.
If unsure, ask your IT team or search "Linux kernel CVE-2021-47438" on the vendor's site.
CVE-2021-47438 (Linux kernel) — CWE-401 / CVSS v3 7.1
Attack vector: local / no user interaction
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.
A vulnerability (CWE-401) exists in Linux kernel.
Check the vendor advisory for the affected versions of Linux kernel.
Severity: High (CVSS 7.1/10). Confidential information can be exposed externally.
Update to the patched release per vendor advisory.
Until the patch is applied: disable the affected feature, apply WAF rules, or restrict access via network ACLs.
Search webserver/proxy logs for unusual request patterns matching this CVE's known IOCs. Audit SBOM/dependencies to find affected services.
Response actions
Concrete steps and command examples for SOC/SRE teams to execute in order
-
1Identify exposure identify
Audit SBOM/dependencies for affected components.資産台帳・SBOM・依存マニフェストで Linux kernel を使っているサービスとバージョンを洗い出す。
-
2Post-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。
Fix status by distribution
Fixed packages published by each distribution for this CVE
- Debian DEBIAN-CVE-2021-47438 linux Fixed in: 5.14.16-1
- Ubuntu UBUNTU-CVE-2021-47438 linux
References
- patch git.kernel.org
- patch git.kernel.org
- patch git.kernel.org