CVE-2026-35606 — v2
CVE-2026-35606 is a CWE-862 vulnerability in github.com/filebrowser/filebrowser/v2. A fix is available for github.com/filebrowser/filebrowser/v2 — see the affected versions and patch details below.
File Browser discloses text file content via /api/resources endpoint bypassing Perm.Download check
Exploitation Status
Proof-of-concept exploit code exists
- CISA’s SSVC triage found public proof-of-concept exploit code for this CVE, though no confirmed active exploitation.
Exploitation and automatability from CISA’s SSVC triage for CVE-2026-35606.
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.
Real-World Exposure
github.com/filebrowser/filebrowser/v2Real-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
File Browser is a file managing interface for uploading, deleting, previewing, renaming, and editing files within a specified directory. Prior to 2.63.1, the resourceGetHandler in http/resource.go returns full text file content without checking the Perm.Download permission flag. All three other content-serving endpoints (/api/raw, /api/preview, /api/subtitle) correctly verify this permission before serving content. A user with download: false can read any text file within their scope through two bypass paths. This vulnerability is fixed in 2.63.1.
Affected Packages
| Ecosystem | Package | Vulnerable range | Fix |
|---|---|---|---|
| 🐹Go | github.com/filebrowser/filebrowser/v2 | all versions | 2.63.1go get github.com/filebrowser/filebrowser/v2@v2.63.1 |
Detection & mitigation playbook
Open-source dependencyDetect
Scan your dependency tree (package-lock.json, pnpm-lock.yaml, requirements.txt, go.sum, etc.) for github.com/filebrowser/filebrowser/v2, including transitive dependencies — a direct dependency you never call can still pull in a vulnerable version.
Fix
Update github.com/filebrowser/filebrowser/v2 to 2.63.1 or later, then make sure no transitive (indirect) dependency still pins the vulnerable range — O3 confirms CVE-2026-35606 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 Security's impact-aware SCA analyses which vulnerable code paths your application actually calls, so a match like CVE-2026-35606 can be triaged on real exposure rather than presence alone.
Tailored to CVE-2026-35606. 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-2026-35606 in your dependencies?
O3 Security finds CVE-2026-35606 across Go dependencies, including transitive ones, and its impact-aware SCA ranks findings by whether your code actually calls the vulnerable path.