CVE-2023-27591
HIGHCVE-2023-27591 is a high-severity (CVSS 7.5) Information Exposure vulnerability in miniflux.app/v2. O3 Security confirms whether CVE-2023-27591 is actually reachable in your code before you act, and blocks exploitation at runtime until you patch.
Unauthenticated Miniflux user can bypass allowed networks check to obtain Prometheus metrics
Blast Radius
miniflux.app/v2🐹miniflux.appReal-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
Miniflux is a feed reader. Prior to version 2.0.43, an unauthenticated user can retrieve Prometheus metrics from a publicly reachable Miniflux instance where the METRICS_COLLECTOR configuration option is enabled and METRICS_ALLOWED_NETWORKS is set to 127.0.0.1/8 (the default). A patch is available in Miniflux 2.0.43. As a workaround, set METRICS_COLLECTOR to false (default) or run Miniflux behind a trusted reverse-proxy.
Affected Packages
| Ecosystem | Package | Vulnerable range | Fix |
|---|---|---|---|
| 🐹Go | miniflux.app/v2 | all versions | 2.0.43 |
| 🐹Go | miniflux.app | 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 miniflux.app/v2. 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 miniflux.app/v2 to 2.0.43 or later, then make sure no transitive (indirect) dependency still pins the vulnerable range — O3 confirms CVE-2023-27591 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-2023-27591 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-2023-27591. 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-2023-27591 in your dependencies?
O3 detects CVE-2023-27591 across Go dependencies and uses function-level reachability to confirm whether the vulnerable code path is actually reachable — not just present. No false positives.