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CVE-2026-42581
medium
CVSS 5.8
Vulnerability in io.netty:netty-codec-http (CVE-2026-42581)
Summary
vulnerability in io.netty:netty-codec-http (CVE-2026-42581). Risk of unauthorized operations or information disclosure. Exploitable via `POST /api`. Mitigation: upgrade to `4.1.133.Final` or later.
AI summary snake-internal / snake-material-v2
A vulnerability tracked as **CVE-2026-42581** has been found in io.netty:netty-codec-http.
Attackers can target a specific entry point like `POST /api` over the network to misuse the product.
Risk of unauthorized operations or information disclosure. CVSS score: 5.8/10.
What to do: upgrade io.netty:netty-codec-http to **4.1.133.Final** or later.
If unsure, ask your IT team or search "io.netty:netty-codec-http CVE-2026-42581" on the vendor's site.
CVE-2026-42581 (io.netty:netty-codec-http) — CWE-444 / CVSS v3 5.8
Attack vector: remote (network-reachable) / unauthenticated / no user interaction
Attack surface: POST /api / `HttpObjectDecoder` / `HttpMessage` / `EmbeddedChannel`
Patched: `4.1.133.Final` — 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** (CWE-444) exists in io.netty:netty-codec-http. Attackers reach the vulnerable code path via `POST /api` without authentication.
📍 Affected scope
io.netty:netty-codec-http — . Attack surface: POST /api / `HttpObjectDecoder` / `HttpMessage` / `EmbeddedChannel`.
🔥 Severity
Severity: Medium (CVSS 5.8/10). Risk of unauthorized operations or information disclosure
🔧 How to fix
Update to **4.1.133.Final**.
🛡️ 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 `POST /api` requests with malformed payloads or SQL meta-characters. Run `grep -r 'io.netty:netty-codec-http' .` against your dependency files (package-lock.json, requirements.txt, go.sum) to find affected services.
Response Actions (7 steps)
Concrete steps and command examples for SOC/SRE teams to execute in order
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1Identify exposure identify
grep -r 'io.netty:netty-codec-http' . | 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 `io.netty:netty-codec-http` を grep し、稼働しているサービス・バージョンを把握する。
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3Hunt for indicators of compromise detect
grep 'POST /api' /var/log/nginx/access.log | grep -E '(unusual_payload|sqli_pattern)'アクセスログで `POST /api` への異常なリクエスト (不正な認証ヘッダ・SQLメタ文字)を過去 30〜90日分捜索。WAF/SIEM があれば該当パスのアラート発火履歴を確認。
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6Apply patch patch
Upgrade io.netty:netty-codec-http to 4.1.133.Finalステージング環境で 4.1.133.Final 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と、Step 3 で見つけた異常検知の続報チェックを含めること。
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7Post-deployment verification verify
Replay attack against POST /api on staging to confirm patch closes the vector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 Step 3 と同じログクエリでアラート再発が無いか継続監視。
Affected packages
maven
io.netty:netty-codec-http
[{"type":"ECOSYSTEM","events":[{"introduced":"0"},{"fixed":"4.1.133.Final"}]}]
References
- advisory https://nvd.nist.gov/vuln/detail/CVE-2026-42581
- exploit 134c704f-9b21-4f2e-91b3-4a467353bcc0
- package https://github.com/netty/netty
- web https://github.com/advisories/GHSA-xxqh-mfjm-7mv9
- web 0b0ca135-0b70-47e7-9f44-1890c2a1c46c
- web 0b0ca135-0b70-47e7-9f44-1890c2a1c46c
- web 0b0ca135-0b70-47e7-9f44-1890c2a1c46c
- web 0b0ca135-0b70-47e7-9f44-1890c2a1c46c
- web 0b0ca135-0b70-47e7-9f44-1890c2a1c46c
- web 0b0ca135-0b70-47e7-9f44-1890c2a1c46c
- web 0b0ca135-0b70-47e7-9f44-1890c2a1c46c