CVE-2026-54562
MEDIUMCloudreve: Non-admin remote download users can SSRF loopback/internal services and read imported responses
EPSS Exploitation Probability
EPSS (Exploit Prediction Scoring System) is a daily probability model maintained by FIRST.org. It estimates the likelihood a CVE will be exploited in production environments within the next 30 days, derived from real-world threat intelligence signals.
Blast Radius
github.com/cloudreve/Cloudreve/v4🐹github.com/cloudreve/Cloudreve/v3Real-time download stats are indexed for npm and PyPI packages. This vulnerability affects Go packages — download data is not available via public APIs for these ecosystems.
Description
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.
Affected Packages
| Ecosystem | Package | Vulnerable range | Fix |
|---|---|---|---|
| 🐹Go | github.com/cloudreve/Cloudreve/v4 | all versions | 4.0.0-20260606025411-aaebf317a78f |
| 🐹Go | github.com/cloudreve/Cloudreve/v3 | all versions | No fix |
Detection & mitigation playbook
Open-source dependencyDetect
Scan your dependency tree (package-lock.json, pnpm-lock.yaml, requirements.txt, go.sum, etc.) for github.com/cloudreve/Cloudreve/v4. O3's reachability analysis confirms whether the vulnerable code path is actually invoked in your application, so you act on real exposure instead of every transitive match.
Fix
Update github.com/cloudreve/Cloudreve/v4 to 4.0.0-20260606025411-aaebf317a78f or later, then make sure no transitive (indirect) dependency still pins the vulnerable range — O3 confirms CVE-2026-54562 is resolved across your whole dependency graph.
Workarounds
If you can't upgrade right away: gate or disable the affected feature, validate untrusted input at the boundary, and avoid passing attacker-controlled data into the vulnerable path. O3's runtime protection blocks exploitation in production as an interim safeguard until the upgrade lands.
How O3 protects you
O3 pinpoints whether CVE-2026-54562 is reachable in your code and exactly where to fix it, then blocks exploitation in production at runtime until the patched version is deployed.
Tailored to CVE-2026-54562. Runtime protection reduces exposure until a permanent patch is applied and verified — it complements patching, it doesn't replace it.
Frequently Asked Questions
Is CVE-2026-54562 in your dependencies?
O3 detects CVE-2026-54562 across Go dependencies and uses function-level reachability to confirm whether the vulnerable code path is actually reachable — not just present. No false positives.