CVE-2021-47986
CVE-2021-47986 is a CWE-494 vulnerability in parse-server. O3 Security confirms whether CVE-2021-47986 is actually reachable in your code before you act, and blocks exploitation at runtime until you patch.
Incorrect version tags linked to external repository
Real-World Exposure
How broadly this vulnerability is actually deployed: weekly install volume shows current usage, a proxy for how much of the ecosystem is exposed.
parse-servernpmDescription
Parse Server before 4.10.0 contains a supply chain vulnerability where incorrect version tags were pushed to the repository linking to unreviewed code in a personal fork. Attackers could exploit this by specifying affected version tags in dependency declarations to execute unreviewed and potentially malicious code.
Affected Packages
| Ecosystem | Package | Vulnerable range | Fix |
|---|---|---|---|
| 📦npm | parse-server | ≥ 4.0.0&&< 4.5.2 | 4.5.2 |
| 📦npm | parse-server | ≥ 4.6.0&&< 4.10.0 | 4.10.0 |
Detection & mitigation playbook
Open-source dependencyDetect
Scan your dependency tree (package-lock.json, pnpm-lock.yaml, requirements.txt, go.sum, etc.) for parse-server. 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 parse-server to 4.5.2 or later, then make sure no transitive (indirect) dependency still pins the vulnerable range — O3 confirms CVE-2021-47986 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-2021-47986 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-2021-47986. 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-2021-47986 in your dependencies?
O3 detects CVE-2021-47986 across npm dependencies and uses function-level reachability to confirm whether the vulnerable code path is actually reachable — not just present. No false positives.