PatchTheCVECVE-2026-66009: Parse Server versions >= 9.0.0 before 9.10.0-alpha.5 and >= 8.2.2 before 8.6.86 return GraphQL validation erro
CVE-2026-66009 is a medium-severity flaw (CVSS 6.3) affecting affected software. Below: why it ranks where it does, which versions are affected, what to do, and the exact commands.
Parse Server versions >= 9.0.0 before 9.10.0-alpha.5 and >= 8.2.2 before 8.6.86 return GraphQL validation error messages that name required custom input fields even when public introspection is disabled (graphQLPublicIntrospection: false, the default). A client holding only the public application id — with no user session, master key, or maintenance key — can trigger validation errors to learn the names of required (non-null) custom fields on cla
Why this priority
- Remotely exploitable, no login, no user action
A fixed release or distro patch exists.
Risk facts
| CVSS score | 6.3 (Medium) |
| Attack vector | Network (remote) |
| Attack complexity | Low |
| Privileges needed | None |
| User interaction | None |
| EPSS exploit chance | 0.4% (top 62%) |
| CISA exploited list | No |
| Weakness | CWE-209 |
| Published | 2026-07-24 |
| Last modified | 2026-10-24 |
Last updated 2026-10-24 · Sources: CVE Program, NVD, CISA KEV, EPSS and vendor advisories · How we score
Timeline
- Published CVE record published
- Updated Record last modified
Exact fixes by distribution
Scores and fixes here are computed automatically from those and other public sources. Confirm with the vendor advisory before changing production systems.
Quick answers
How do I fix CVE-2026-66009?
No fixed release is listed yet. Watch the vendor advisory and apply any mitigation shown on this page.
Is CVE-2026-66009 being exploited?
CVE-2026-66009 is not on the CISA Known Exploited Vulnerabilities list at the time of the last update. Check again, as this can change.
What does CVE-2026-66009 affect?
CVE-2026-66009 affects affected software. Severity is medium (CVSS 6.3). Parse Server versions >= 9.0.0 before 9.10.0-alpha.5 and >= 8.2.2 before 8.6.86 return GraphQL validation error messages that name required custom input fields even when public introspection is disabled (graphQLPublicIntrospection: false, t
How urgent is CVE-2026-66009?
Priority 36/100. Remotely exploitable, no login, no user action