Cross-Site Scripting (XSS) in Seafile (CVE-2026-30587)
Summary
Cross-site scripting in Seafile (CVE-2026-30587). Confidential information can be exposed externally. Mitigation: upgrade to 13.0.17 or later.
Original description
The description as published by the source.
Multiple Stored XSS vulnerabilities exist in Seafile Server version 13.0.15,13.0.16-pro,12.0.14 and prior and fixed in 13.0.17, 13.0.17-pro, and 12.0.20-pro, via the Seadoc (sdoc) editor. The application fails to properly sanitize WebSocket messages regarding document structure updates. This allows authenticated remote attackers to inject malicious JavaScript payloads via the src attribute of embedded Excalidraw whiteboards or the href attribute of anchor tags
Source: NIST National Vulnerability Database NVD GitHub Advisory
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-2026-30587 has been found in Seafile.
Confidential information can be exposed externally. CVSS score: 8.7/10.
What to do: upgrade Seafile to 13.0.17 or later.
If unsure, ask your IT team or search "Seafile CVE-2026-30587" on the vendor's site.
CVE-2026-30587 (Seafile) — CWE-79 / CVSS v3 8.7
Attack vector: remote (network-reachable)
Patched: 13.0.17 — 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.
Cross-site scripting (XSS) (CWE-79) exists in Seafile.
Check the vendor advisory for the affected versions of Seafile.
Severity: High (CVSS 8.7/10). Confidential information can be exposed externally.
Update to 13.0.17.
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. Run grep -r 'Seafile' . 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
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1Identify exposure identify
grep -r 'Seafile' . | 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
Seafileを grep し、稼働しているサービス・バージョンを把握する。 -
2Apply patch patch
Upgrade Seafile to 13.0.17ステージング環境で 13.0.17 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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3Post-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。
References
- advisory github.com
- advisory nvd.nist.gov
- patch github.com
- patch github.com
- web gist.github.com
- web manual.seafile.com
- web manual.seafile.com
- web manual.seafile.com