GHSA-rwxp-hwwf-653v is a medium-severity (CVSS 5.4) Information Exposure vulnerability in express-hbs. 1 public exploit reference exists, so weaponization risk is real. O3 Security confirms whether GHSA-rwxp-hwwf-653v is actually reachable in your code before you act, and blocks exploitation at runtime until you patch.
Insecure template handling in express-hbs
Real-World Exposure
How broadly this vulnerability is actually deployed: weekly install volume shows current usage, and reverse-dependency count shows how many other packages break if it stays unpatched.
express-hbsnpmDescription
express-hbs is an Express handlebars template engine. express-hbs mixes pure template data with engine configuration options through the Express render API. More specifically, the layout parameter may trigger file disclosure vulnerabilities in downstream applications. This potential vulnerability is somewhat restricted in that only files with existing extentions (i.e. file.extension) can be included, files that lack an extension will have .hbs appended to them. For complete details refer to the referenced GHSL-2021-019 report. Notes in documentation have been added to help users of express-hbs avoid this potential information exposure vulnerability.
Affected Packages
| Ecosystem | Package | Vulnerable range | Fix |
|---|---|---|---|
| 📦npm | express-hbs | all versions | No fix |
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 express-hbs. 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.
Remediation status
No patched version of express-hbs has shipped for GHSA-rwxp-hwwf-653v yet. Where your build allows, override or pin the dependency away from the vulnerable range, and apply any maintainer-recommended mitigation.
Mitigate without a patch
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-rwxp-hwwf-653v 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-rwxp-hwwf-653v. 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-rwxp-hwwf-653v in your dependencies?
O3 detects GHSA-rwxp-hwwf-653v across npm dependencies and uses function-level reachability to confirm whether the vulnerable code path is actually reachable — not just present. No false positives.