CVE-2026-30966 — parse-server
CRITICALCVE-2026-30966 is a critical-severity (CVSS 10) vulnerability in parse-server. A fix is available for parse-server — see the affected versions and patch details below.
Parse Server role escalation and CLP bypass via direct `_Join` table write
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-2026-30966.
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-2026-30966 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 379,145 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
Parse Server's internal tables, which store Relation field mappings such as role memberships, can be directly accessed via the REST API or GraphQL API by any client using only the application key. No master key is required.
An attacker can create, read, update, or delete records in any internal relationship table. Exploiting this allows the attacker to inject themselves into any Parse Role, gaining all permissions associated with that role, including full read, write, and delete access to classes protected by role-based Class-Level Permissions (CLP). Similarly, writing to any such table that backs a Relation field used in a pointerFields CLP bypasses that access control.
Patches
The fix blocks direct client access to internal relationship tables in Parse Server's role security enforcement. All create, find, get, update, and delete operations on these tables now require the master key or maintenance key.
Workarounds
There is no known workaround.
References
- GitHub security advisory: https://github.com/parse-community/parse-server/security/advisories/GHSA-5f92-jrq3-28rc
- Fix Parse Server 9: https://github.com/parse-community/parse-server/releases/tag/9.5.2-alpha.7
- Fix Parse Server 8: https://github.com/parse-community/parse-server/releases/tag/8.6.20
Affected Packages
| Ecosystem | Package | Vulnerable range | Fix |
|---|---|---|---|
| 📦npm | parse-server | ≥ 9.0.0-alpha.1&&< 9.5.2-alpha.7 | 9.5.2-alpha.7npm install parse-server@9.5.2-alpha.7 |
| 📦npm | parse-server | all versions | 8.6.20npm install parse-server@8.6.20 |
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 9.5.2-alpha.7 or later, then make sure no transitive (indirect) dependency still pins the vulnerable range — O3 confirms CVE-2026-30966 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-2026-30966 can be triaged on real exposure rather than presence alone.
Tailored to CVE-2026-30966. 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-2026-30966 in your dependencies?
O3 Security finds CVE-2026-30966 across npm dependencies, including transitive ones, and its impact-aware SCA ranks findings by whether your code actually calls the vulnerable path.