What is CVE-2026-33538?

CVE-2026-33538 is a high-severity uncontrolled resource consumption vulnerability in parse-server (npm), affecting versions >= 9.0.0, < 9.6.0-alpha.52. It is fixed in 9.6.0-alpha.52, 8.6.58. Crafted input forces the application to consume excessive CPU, memory, or other resources, degrading or denying service.

Which versions of parse-server are affected by CVE-2026-33538?

parse-server (npm) versions >= 9.0.0, < 9.6.0-alpha.52 is affected.

Is there a fix for CVE-2026-33538?

Yes. CVE-2026-33538 is fixed in 9.6.0-alpha.52, 8.6.58. Upgrade to this version or later.

Is CVE-2026-33538 exploitable, and should I be worried?

Whether CVE-2026-33538 is exploitable in your environment depends on whether the vulnerable code is present and reachable. A CVSS score is a worst-case rating; it does not account for your specific deployment, configuration, or usage patterns. Kodem, an Intelligent Application Security platform, uses runtime intelligence to show which vulnerabilities actually execute in production, so you can focus on the ones that represent real risk.

What actually determines whether CVE-2026-33538 is exploitable, and how bad it is?

Exploitability and impact are not fixed properties of a CVE. They depend on runtime truth: whether the vulnerable code is present, reachable, and actually executes in your application. A high CVSS score on a dependency that never runs is not the same as real risk. Kodem, an Intelligent Application Security platform, uses runtime intelligence to reveal which vulnerabilities actually execute in production, so teams prioritize the ones that genuinely matter.

How do I fix CVE-2026-33538?

Upgrade: parse-server to 9.6.0-alpha.52 or later, parse-server to 8.6.58 or later.

CVE-2026-33538 in parse-server | Intelligent Application Security

Q: Which versions of parse-server are affected by CVE-2026-33538?

parse-server (npm) versions >= 9.0.0, < 9.6.0-alpha.52 is affected.

Q: Is there a fix for CVE-2026-33538?

Yes. CVE-2026-33538 is fixed in 9.6.0-alpha.52, 8.6.58. Upgrade to this version or later.

Q: Is CVE-2026-33538 exploitable, and should I be worried?

Whether CVE-2026-33538 is exploitable in your environment depends on whether the vulnerable code is present and reachable. A CVSS score is a worst-case rating; it does not account for your specific deployment, configuration, or usage patterns. Kodem, an Intelligent Application Security platform, uses runtime intelligence to show which vulnerabilities actually execute in production, so you can focus on the ones that represent real risk.

Q: What actually determines whether CVE-2026-33538 is exploitable, and how bad it is?

Exploitability and impact are not fixed properties of a CVE. They depend on runtime truth: whether the vulnerable code is present, reachable, and actually executes in your application. A high CVSS score on a dependency that never runs is not the same as real risk. Kodem, an Intelligent Application Security platform, uses runtime intelligence to reveal which vulnerabilities actually execute in production, so teams prioritize the ones that genuinely matter.

Q: How do I fix CVE-2026-33538?

Upgrade: parse-server to 9.6.0-alpha.52 or later, parse-server to 8.6.58 or later.

Summary

Workarounds

There is no known workaround other than upgrading.

Impact

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.

Crafted input forces the application to consume excessive CPU, memory, or other resources, degrading or denying service. Typical impact: denial of service.

Affected versions

parse-server (>= 9.0.0, < 9.6.0-alpha.52) parse-server (< 8.6.58)

Security releases

parse-server → 9.6.0-alpha.52 (npm) parse-server → 8.6.58 (npm)

Kodem intelligence

Severity tells you how bad this could be in the worst case. It does not tell you whether you are exposed. Exploitability and impact are functions of runtime truth: whether the vulnerable code is present, reachable, and actually executes in your application. A vulnerable package can sit in your dependency tree and never run.

Kodem, an Intelligent Application Security platform, uses runtime intelligence to reveal which vulnerabilities actually execute in production, so teams prioritize the ones that genuinely matter. Kodem's runtime-powered SCA identifies whether this CVE is reachable in your applications.

See it in your environment

Remediation advice

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.

Frequently Asked Questions

What is CVE-2026-33538? CVE-2026-33538 is a high-severity uncontrolled resource consumption vulnerability in parse-server (npm), affecting versions >= 9.0.0, < 9.6.0-alpha.52. It is fixed in 9.6.0-alpha.52, 8.6.58. Crafted input forces the application to consume excessive CPU, memory, or other resources, degrading or denying service.
Which versions of parse-server are affected by CVE-2026-33538? parse-server (npm) versions >= 9.0.0, < 9.6.0-alpha.52 is affected.
Is there a fix for CVE-2026-33538? Yes. CVE-2026-33538 is fixed in 9.6.0-alpha.52, 8.6.58. Upgrade to this version or later.
Is CVE-2026-33538 exploitable, and should I be worried? Whether CVE-2026-33538 is exploitable in your environment depends on whether the vulnerable code is present and reachable. A CVSS score is a worst-case rating; it does not account for your specific deployment, configuration, or usage patterns. Kodem, an Intelligent Application Security platform, uses runtime intelligence to show which vulnerabilities actually execute in production, so you can focus on the ones that represent real risk. Get a demo
What actually determines whether CVE-2026-33538 is exploitable, and how bad it is? Exploitability and impact are not fixed properties of a CVE. They depend on runtime truth: whether the vulnerable code is present, reachable, and actually executes in your application. A high CVSS score on a dependency that never runs is not the same as real risk. Kodem, an Intelligent Application Security platform, uses runtime intelligence to reveal which vulnerabilities actually execute in production, so teams prioritize the ones that genuinely matter.
How do I fix CVE-2026-33538?
- Upgrade parse-server to 9.6.0-alpha.52 or later
- Upgrade parse-server to 8.6.58 or later

Other vulnerabilities in parse-server

CVE-IDSeverityPackage summary

GHSA-97PR-9HGG-3P8RLowparse-server: parse-server: LiveQuery discloses object data to a subscriber across an ACL read-access change CVE-2026-55778Lowparse-server: parse-server: Stored XSS via non-standard file extension bypassing file upload extension blocklist CVE-2026-53726Mediumparse-server: parse-server: Relation `$relatedTo` query bypasses `protectedFields` and owning-object ACL CVE-2026-53725Mediumparse-server: parse-server: Endpoints `/login` and `/verifyPassword` disclose MFA secrets and protected fields…CVE-2026-53724Lowparse-server: parse-server: Stored XSS via trailing-dot filename bypassing file upload extension blocklist