Vulnerability in Kyoo (CVE-2026-77385)
Summary
Vulnerability in Kyoo (CVE-2026-77385). Risk of unauthorized operations or information disclosure. Mitigation: upgrade to 5.1.0 or later.
Original description
The description as published by the source.
Kyoo is a self-hosted media server focused on movies, series, and anime. Prior to 5.1.0, a registered user with the core.play permission could supply a base64-encoded filesystem path to the transcoder. The path handling in transcoder/src/api/path.go cleaned the value and checked only that it began with Settings.SafePath before getHash processed it, while transcoder/src/api/streams.go served the accepted path without verifying a Kyoo catalog record. This missing catalog-level authorization allowed the user to retrieve hidden, temporary, operational, or other uncataloged files beneath the media directory when the path was known or guessed. This vulnerability is fixed in 5.1.0.
Source: NIST National Vulnerability Database NVD
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-2026-77385 has been found in Kyoo.
Risk of unauthorized operations or information disclosure. CVSS score: 4.3/10.
What to do: upgrade Kyoo to 5.1.0 or later.
If unsure, ask your IT team or search "Kyoo CVE-2026-77385" on the vendor's site.
CVE-2026-77385 (Kyoo) — CWE-639 / CVSS v3 4.3
Attack vector: remote (network-reachable) / no user interaction
Patched: 5.1.0 — 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.
A vulnerability (CWE-639) exists in Kyoo.
Check the vendor advisory for the affected versions of Kyoo.
Severity: Medium (CVSS 4.3/10). Risk of unauthorized operations or information disclosure.
Update to 5.1.0.
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 'Kyoo' . 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 'Kyoo' . | 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
Kyoo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 Kyoo to 5.1.0ステージング環境で 5.1.0 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。