Parse Server is an open source backend that can be deployed to any infrastructure that can run Node.js. Prior to versions 8.6.58 and 9.6.0-alpha.52, an unauthenticated attacker can cause denial of service by sending authentication requests with arbitrary, unconfigured provider names. The server executes a database query for each unconfigured provider before rejecting the request, and since no database index exists for unconfigured providers, each request triggers a full collection scan on the user database. This can be parallelized to saturate database resources. This issue has been patched in versions 8.6.58 and 9.6.0-alpha.52.
PUBLISHED5.2CWE-400
Parse Server: Denial of service via unindexed database query for unconfigured auth providers
Problem type
Affected products
parse-community
parse-server
< 8.6.58 - AFFECTED
>= 9.0.0, < 9.6.0-alpha.52 - AFFECTED
References
https://github.com/parse-community/parse-server/security/advisories/GHSA-g4cf-xj29-wqqr
https://github.com/parse-community/parse-server/security/advisories/GHSA-g4cf-xj29-wqqr
https://github.com/parse-community/parse-server/pull/10270
https://github.com/parse-community/parse-server/pull/10270
https://github.com/parse-community/parse-server/pull/10271
https://github.com/parse-community/parse-server/pull/10271
https://github.com/parse-community/parse-server/commit/40eb442e02672986730007d0a1edb22c1c4bd357
https://github.com/parse-community/parse-server/commit/40eb442e02672986730007d0a1edb22c1c4bd357
https://github.com/parse-community/parse-server/commit/fbac847499e57f243315c5fc7135be1d58bb8e54
https://github.com/parse-community/parse-server/commit/fbac847499e57f243315c5fc7135be1d58bb8e54
GitHub Security Advisories
GHSA-g4cf-xj29-wqqr
Parse Server: Denial of Service via unindexed database query for unconfigured auth providers
https://github.com/advisories/GHSA-g4cf-xj29-wqqrImpact
An unauthenticated attacker can cause Denial of Service by sending authentication requests with arbitrary, unconfigured provider names. The server executes a database query for each unconfigured provider before rejecting the request, and since no database index exists for unconfigured providers, each request triggers a full collection scan on the user database. This can be parallelized to saturate database resources.
Patches
The fix validates that an authentication provider is configured before executing any database query. Requests with unconfigured providers are now rejected immediately without querying the database.
Workarounds
There is no known workaround other than upgrading.
JSON source
https://cveawg.mitre.org/api/cve/CVE-2026-33538Click to expand
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