GHSA-4j89-2c4f-44c6
LOWGogs has DoS in rendering issue index pattern
Blast Radius
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
Summary
Special template of issue index pattern may cause panic.
Details
in internal/markup/markup.go
link = fmt.Sprintf(`<a href="%s">%s</a>`, com.Expand(metas["format"], metas), m)
Issue index pattern is rendered to link with com.Expand.
However, com.Expand is not safe.
i = strings.Index(template, "}")
if s, ok := match[template[:i]]; ok {
when { is found but } not found, i comes to 1, template[:-1] will be called, and then panicked
finally, all pages than contains issue index are unavailable.
PoC
- set issue index pattern as follow
- add a commit which point to an issue in its msg
using #1 above
Impact
DoS that cause part of pages of the specify repo unavailable.
Affected Packages
| Ecosystem | Package | Vulnerable range | Fix |
|---|---|---|---|
| 🐹Go | gogs.io/gogs | all versions | 0.14.3 |
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. 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 gogs.io/gogs to 0.14.3 or later, then make sure no transitive (indirect) dependency still pins the vulnerable range — O3 confirms GHSA-4j89-2c4f-44c6 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 GHSA-4j89-2c4f-44c6 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 GHSA-4j89-2c4f-44c6. Runtime protection reduces exposure until a permanent patch is applied and verified — it complements patching, it doesn't replace it.
Frequently Asked Questions
Is GHSA-4j89-2c4f-44c6 in your dependencies?
O3 detects GHSA-4j89-2c4f-44c6 across Go dependencies and uses function-level reachability to confirm whether the vulnerable code path is actually reachable — not just present. No false positives.