← Back
CVE-2026-42193
critical
CVSS 9.1
Vulnerability in aws (CVE-2026-42193)
Summary
vulnerability in aws (CVE-2026-42193). Data can be tampered with by attackers.
AI summary openai / gpt-4o
A vulnerability in Plunk, an open-source email platform, allows attackers to spoof SNS notifications. This can result in the manipulation of automated workflows, unsubscribing contacts, and altering email metrics. Systems running versions below 0.9.0 are affected, and an immediate update is recommended to mitigate the risk.
The vulnerability CVE-2026-42193 in Plunk's /webhooks/sns endpoint arises from not verifying Amazon SNS signatures, certificates, or topic ARNs. This allows unauthenticated spoofing of SNS events, enabling the abuse of automated workflows. Versions affected are below 0.9.0, and the issue is patched in 0.9.0. Applying the update addresses the risk. Detection can involve monitoring logs for anomalous event activity related to spoofed SNS events.
❓ What is the problem
/webhooks/sns endpoint in Plunk fails to verify SNS signature, certificate, or topic ARN.
📍 Affected scope
Plunk versions <0.9.0.
🔥 Severity
Critical. Allows unauthenticated spoofing of SNS events to disrupt platform functionality.
🔧 How to fix
Upgrade Plunk to version 0.9.0.
🛡️ Workaround
素材から特定できず。
🔍 Detection
Check logs for unexpected SNS event patterns or anomalies.
Related past incidents Similar incidents extracted from past CVEs
SNS signature verification bypass leading to forgery in another AWS service.
If this happens at your company Expected impact per business scenario
📌 企業のメールマーケティングシステム
偽のSNS通知によりキャンペーンの停止や分析データの改ざん
📌 中小企業の情報システム
誤った通知をトリガーし、自動化された処理の誤作動
📌 サブスクリプション型Webサービス
顧客を誤って解除し、カスタマーエクスペリエンスが低下
Recommended action
直ちにプラットフォームをバージョン0.9.0にアップデートし、潜在的な不正なSNS通知を検知するためのログ監視を強化する。
Response Actions (7 steps)
Concrete steps and command examples for SOC/SRE teams to execute in order
-
1Identify exposure identify
Audit SBOM/dependencies for affected components.依存マニフェストで影響コンポーネントを特定する。
-
2Match against affected range verify
Confirm if version satisfies `< 0.8.0`Step 1 で見つかったバージョンが影響範囲 `< 0.8.0` に該当するか照合。本番で稼働中ならインシデント扱い。
-
7Post-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 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。
References
- web [email protected]
- web [email protected]