Vulnerability in xorg-server (ALPINE-CVE-2021-3472)

Summary

Vulnerability in xorg-server (ALPINE-CVE-2021-3472). Successful exploitation can lead to full system takeover. Mitigation: upgrade to 1.20.5-r3 or later.

Original description

The description as published by the source.

A flaw was found in xorg-x11-server in versions before 1.20.11. An integer underflow can occur in xserver which can lead to a local privilege escalation. The highest threat from this vulnerability is to data confidentiality and integrity as well as system availability.

Source: OSV.dev (Open Source Vulnerabilities) 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 ALPINE-CVE-2021-3472 has been found in xorg-server.
Successful exploitation can lead to full system takeover.
What to do: upgrade xorg-server to 1.20.5-r3 or later.
If unsure, ask your IT team or search "xorg-server ALPINE-CVE-2021-3472" on the vendor's site.

ALPINE-CVE-2021-3472 (xorg-server)
Attack vector: local / no user interaction
Patched: 1.20.5-r3 — 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 xorg-server.

📍 Affected scope

Check the vendor advisory for the affected versions of xorg-server.

🔥 Severity

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

🔧 How to fix

Update to 1.20.5-r3.

🛡️ 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 'xorg-server' . 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 'xorg-server' . | 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 xorg-server 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 xorg-server to 1.20.5-r3
```
ステージング環境で 1.20.5-r3 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

Alpine:v3.10 xorg-server

[{"type":"ECOSYSTEM","events":[{"introduced":"0"},{"fixed":"1.20.5-r3"}]}]

Alpine:v3.11 xorg-server

[{"type":"ECOSYSTEM","events":[{"introduced":"0"},{"fixed":"1.20.6-r3"}]}]

Alpine:v3.12 xorg-server

[{"type":"ECOSYSTEM","events":[{"introduced":"0"},{"fixed":"1.20.10-r1"}]}]

References

advisory security.alpinelinux.org