CVE-2018-20303 is a high-severity (CVSS 7.5) Path Traversal vulnerability in gogs.io/gogs. 1 public exploit reference exists, so weaponization risk is real. A fix is available for gogs.io/gogs — see the affected versions and patch details below.
Gogs Directory Traversal
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.
How urgent is this, really
CVE-2018-20303 plotted by exploitation likelihood (EPSS) against impact (CVSS). The shaded corner — EPSS 50%+ and CVSS 7.0+ — is where this CVE doesn't sit, though severity or exploitability alone can still warrant action.
Where this sits among everything scored
Of 377,636 CVEs with a current EPSS score, this one falls in the < 10% band (highlighted). Real counts from FIRST.org, not a sample — log-scaled since the landscape is heavily right-skewed.
Real-World Exposure
gogs.io/gogsReal-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
In pkg/tool/path.go in Gogs before 0.11.82.1218, a directory traversal in the file-upload functionality can allow an attacker to create a file under data/sessions on the server, a similar issue to CVE-2018-18925.
Affected Packages
| Ecosystem | Package | Vulnerable range | Fix |
|---|---|---|---|
| 🐹Go | gogs.io/gogs | all versions | 0.11.80-0.20181218063808-ff93d9dbda5cgo get gogs.io/gogs@v0.11.80-0.20181218063808-ff93d9dbda5c |
Research use only. For defensive security, authorized penetration testing, and academic research only. Never execute exploit code against systems without explicit written authorization.
Detection & mitigation playbook
Open-source dependencyDetect
Scan your dependency tree (package-lock.json, pnpm-lock.yaml, requirements.txt, go.sum, etc.) for gogs.io/gogs, including transitive dependencies — a direct dependency you never call can still pull in a vulnerable version.
Fix
Update gogs.io/gogs to 0.11.80-0.20181218063808-ff93d9dbda5c or later, then make sure no transitive (indirect) dependency still pins the vulnerable range — O3 confirms CVE-2018-20303 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-2018-20303 can be triaged on real exposure rather than presence alone.
Tailored to CVE-2018-20303. 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-2018-20303 in your dependencies?
O3 Security finds CVE-2018-20303 across Go dependencies, including transitive ones, and its impact-aware SCA ranks findings by whether your code actually calls the vulnerable path.