[KEV] Vulnerability in Linux Kernel (CVE-2021-22600)
Summary
Vulnerability in Linux Kernel (CVE-2021-22600). Risk of unauthorized operations or information disclosure. Listed in CISA KEV — actively exploited. Mitigation: upgrade to :2022-05-05 or later.
Original description
The description as published by the source.
In packet_set_ring of af_packet.c, there is a possible memory corruption due to a use after free. This could lead to local escalation of privilege with System execution privileges needed. User interaction is not needed for exploitation.
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-2021-22600 has been found in Linux Kernel.
Risk of unauthorized operations or information disclosure.
Note: CISA has officially confirmed this is actively exploited in the wild. Treat it with elevated urgency.
What to do: upgrade Linux Kernel to :2022-05-05 or later.
If unsure, ask your IT team or search "Linux Kernel CVE-2021-22600" on the vendor's site.
CVE-2021-22600 (Linux Kernel) — CWE-415
Patched: :2022-05-05 — apply immediately
Listed in CISA KEV — actively exploited, treat as top priority.
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-415) exists in Linux Kernel.
Check the vendor advisory for the affected versions of Linux Kernel.
Severity: High. Risk of unauthorized operations or information disclosure. Listed in CISA KEV — actively exploited in the wild, treat as top priority.
Update to :2022-05-05.
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
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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。
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2Consider incident declaration escalate
Notify SOC / on-callCISA KEV登録済 = 実環境で悪用が観測されている。侵入の兆候があればインシデント対応宣言、無くてもパッチ適用までWAF強化を最優先で。
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3Apply patch patch
Upgrade Linux Kernel to :2022-05-05ステージング環境で :2022-05-05 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。
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4Post-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
Fix status by distribution
Fixed packages published by each distribution for this CVE
- Debian DEBIAN-CVE-2021-22600 linux Fixed in: 5.15.15-1
- Ubuntu UBUNTU-CVE-2021-22600 linux-azure Fixed in: 4.15.0-1131.144~14.04.1
References
- advisory NVD
- advisory source.android.com
- advisory source.android.com
- patch android.googlesource.com