CVE-2026-30967 — parse-server
CVE-2026-30967 is a Improper Authentication vulnerability in parse-server. A fix is available for parse-server — see the affected versions and patch details below.
Parse Server OAuth2 authentication adapter account takeover via identity spoofing
Exploitation Status
No confirmed exploitation observed yet
- 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-2026-30967.
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.
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
The OAuth2 authentication adapter, when configured without the useridField option, only verifies that a token is active via the provider's token introspection endpoint, but does not verify that the token belongs to the user identified by authData.id. An attacker with any valid OAuth2 token from the same provider can authenticate as any other user.
This affects any Parse Server deployment that uses the generic OAuth2 authentication adapter (configured with oauth2: true) without setting the useridField option.
Patches
The vulnerability is fixed by defaulting useridField to sub, which is the standard subject identifier field defined by RFC 7662. The adapter now always validates the token's identity against the claimed user ID, even when useridField is not explicitly configured.
Workarounds
Set the useridField option to the appropriate field name for your OAuth2 provider (e.g. sub) in the Parse Server authentication configuration.
References
- GitHub security advisory: https://github.com/parse-community/parse-server/security/advisories/GHSA-fr88-w35c-r596
- Fix Parse Server 9: https://github.com/parse-community/parse-server/releases/tag/9.5.2-alpha.9
- Fix Parse Server 8: https://github.com/parse-community/parse-server/releases/tag/8.6.22
Affected Packages
| Ecosystem | Package | Vulnerable range | Fix |
|---|---|---|---|
| 📦npm | parse-server | ≥ 9.0.0-alpha.1&&< 9.5.2-alpha.9 | 9.5.2-alpha.9npm install parse-server@9.5.2-alpha.9 |
| 📦npm | parse-server | all versions | 8.6.22npm install parse-server@8.6.22 |
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.9 or later, then make sure no transitive (indirect) dependency still pins the vulnerable range — O3 confirms CVE-2026-30967 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-2026-30967 can be triaged on real exposure rather than presence alone.
Tailored to CVE-2026-30967. 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-2026-30967 in your dependencies?
O3 Security finds CVE-2026-30967 across npm dependencies, including transitive ones, and its impact-aware SCA ranks findings by whether your code actually calls the vulnerable path.