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CVE-2026-55839
high
CVSS 8.7
Cross-Site Scripting (XSS) in io.kestra:kestra (CVE-2026-55839)
Summary
cross-site scripting in io.kestra:kestra (CVE-2026-55839). Confidential information can be exposed externally. Exploitable via ``onclick``. Mitigation: upgrade to `1.3.24` or later.
AI summary snake-internal / snake-material-v2
A vulnerability tracked as **CVE-2026-55839** has been found in io.kestra:kestra.
Attackers can target a specific entry point like ``onclick`` over the network to misuse the product.
Confidential information can be exposed externally. CVSS score: 8.7/10.
What to do: upgrade io.kestra:kestra to **1.3.24** or later.
If unsure, ask your IT team or search "io.kestra:kestra CVE-2026-55839" on the vendor's site.
CVE-2026-55839 (io.kestra:kestra) — CWE-79 / CVSS v3 8.7
Attack vector: remote (network-reachable)
Attack surface: `onclick` / `onmouseover` / `onfocus` / `style`
Patched: `1.3.24` — 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
**Cross-site scripting (XSS)** (CWE-79) exists in io.kestra:kestra. Attackers reach the vulnerable code path via ``onclick`` without authentication.
📍 Affected scope
io.kestra:kestra — . Attack surface: `onclick` / `onmouseover` / `onfocus` / `style`.
🔥 Severity
Severity: High (CVSS 8.7/10). Confidential information can be exposed externally
🔧 How to fix
Update to **1.3.24**.
🛡️ 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 'io.kestra:kestra' .` 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.kestra:kestra' . | 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.kestra:kestra` 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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6Apply patch patch
Upgrade io.kestra:kestra to 1.3.24ステージング環境で 1.3.24 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
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。
Affected packages
maven
io.kestra:kestra
[{"type":"ECOSYSTEM","events":[{"introduced":"0"},{"fixed":"1.3.24"}]}]