SSRF (Server-Side Request Forgery) in github.com/cloudreve/Cloudreve/v4 (CVE-2026-54562)
Summary
SSRF in github.com/cloudreve/Cloudreve/v4 (CVE-2026-54562). Confidential information can be exposed externally. Exploitable via POST /api/v4/workflow/download. Mitigation: upgrade to 4.0.0-20260606025411-aaebf317a78f or later.
Original description
The description as published by the source.
Cloudreve is a self-hosted file management and sharing system. Prior to 4.16.1, Cloudreve's remote download workflow accepts user-supplied URLs at POST /api/v4/workflow/download and passes them to the configured downloader without blocking loopback, localhost, IPv6 localhost, or redirect-to-loopback targets, allowing a non-admin user with remote download permission to fetch internal-only URLs and read the response after it is imported into the user's own files. This issue is fixed in version 4.16.1.
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-2026-54562 has been found in github.com/cloudreve/Cloudreve/v4.
Attackers can target a specific entry point like POST /api/v4/workflow/download over the network to misuse the product.
Confidential information can be exposed externally. CVSS score: 6.5/10.
What to do: upgrade github.com/cloudreve/Cloudreve/v4 to 4.0.0-20260606025411-aaebf317a78f or later.
If unsure, ask your IT team or search "github.com/cloudreve/Cloudreve/v4 CVE-2026-54562" on the vendor's site.
CVE-2026-54562 (github.com/cloudreve/Cloudreve/v4) — CWE-918 / CVSS v3 6.5
Attack vector: remote (network-reachable) / no user interaction
Attack surface: POST /api/v4/workflow/download / GET /api/v4/workflow / GET /api/v4/file / POST /api/v4/file/url
Patched: 4.0.0-20260606025411-aaebf317a78f — 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.
SSRF (CWE-918) exists in github.com/cloudreve/Cloudreve/v4. Attackers reach the vulnerable code path via POST /api/v4/workflow/download.
Check the vendor advisory for the affected versions of github.com/cloudreve/Cloudreve/v4. Attack surface: POST /api/v4/workflow/download / GET /api/v4/workflow / GET /api/v4/file / POST /api/v4/file/url.
Severity: Medium (CVSS 6.5/10). Confidential information can be exposed externally.
Update to 4.0.0-20260606025411-aaebf317a78f.
Until the patch is applied: disable the affected feature, apply WAF rules, or restrict access via network ACLs.
Search webserver/proxy logs for unusual POST /api/v4/workflow/download requests with malformed payloads or SQL meta-characters. Run grep -r 'github.com/cloudreve/Cloudreve/v4' . 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
-
1Identify exposure identify
grep -r 'github.com/cloudreve/Cloudreve/v4' . | 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
github.com/cloudreve/Cloudreve/v4を grep し、稼働しているサービス・バージョンを把握する。 -
2Hunt for indicators of compromise detect
grep 'POST /api/v4/workflow/download' /var/log/nginx/access.log | grep -E '(unusual_payload|sqli_pattern)'アクセスログで
POST /api/v4/workflow/download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。 -
3Apply patch patch
Upgrade github.com/cloudreve/Cloudreve/v4 to 4.0.0-20260606025411-aaebf317a78fステージング環境で 4.0.0-20260606025411-aaebf317a78f 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 2 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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4Post-deployment verification verify
Replay attack against POST /api/v4/workflow/download 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 2 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
References
- advisory github.com
- advisory nvd.nist.gov
- advisory github.com
- package github.com
- patch github.com
- web github.com
- web github.com