CVE-2023-36475 is a critical-severity (CVSS 9.8) CWE-1321 vulnerability in parse-server. A fix is available for parse-server — see the affected versions and patch details below.
Parse Server vulnerable to remote code execution via MongoDB BSON parser through prototype pollution
Exploitation Status
No confirmed exploitation observed yet
- CISA assesses this as automatable — exploitation doesn’t require manual, per-target effort, which raises the odds of mass scanning and opportunistic attacks.
- A successful exploit gives an attacker total control of the affected component, not partial access.
- CISA’s own triage has not observed active exploitation or public proof-of-concept code for this CVE as of its last assessment.
Exploitation and automatability from CISA’s SSVC triage for CVE-2023-36475.
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-2023-36475 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 378,156 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
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.
parse-servernpmDescription
Impact
An attacker can use this prototype pollution sink to trigger a remote code execution through the MongoDB BSON parser.
Patches
Prevent prototype pollution in MongoDB database adapter.
Workarounds
Disable remote code execution through the MongoDB BSON parser.
Credits
- Discovered by hir0ot working with Trend Micro Zero Day Initiative
- Fixed by dbythy
- Reviewed by mtrezza
References
Affected Packages
| Ecosystem | Package | Vulnerable range | Fix |
|---|---|---|---|
| 📦npm | parse-server | all versions | 5.5.2npm install parse-server@5.5.2 |
| 📦npm | parse-server | ≥ 6.0.0&&< 6.2.1 | 6.2.1npm install parse-server@6.2.1 |
Detection & mitigation playbook
Open-source dependencyDetect
Scan your dependency tree (package-lock.json, pnpm-lock.yaml, requirements.txt, go.sum, etc.) for parse-server, including transitive dependencies — a direct dependency you never call can still pull in a vulnerable version.
Fix
Update parse-server to 5.5.2 or later, then make sure no transitive (indirect) dependency still pins the vulnerable range — O3 confirms CVE-2023-36475 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-2023-36475 can be triaged on real exposure rather than presence alone.
Tailored to CVE-2023-36475. 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-2023-36475 in your dependencies?
O3 Security finds CVE-2023-36475 across npm dependencies, including transitive ones, and its impact-aware SCA ranks findings by whether your code actually calls the vulnerable path.