GHSA-cgxm-vr2f-6fj8: parse-server Denial of Service Vulnerability

HIGH
Share
CWE-407
Published
Advisory Summary

GHSA-cgxm-vr2f-6fj8 is a HIGH denial of service vulnerability (CWE-407: Inefficient Algorithmic Complexity) affecting parse-server libraries in the npm ecosystem. The issue involves denial of service via exponential-time processing of deeply nested query operators. Remediation is available by upgrading affected packages to version 9.9.1-alpha.12, 8.6.82.

GHSA-cgxm-vr2f-6fj8 at a Glance

CVE Identifier N/A
GHSA Identifier GHSA-cgxm-vr2f-6fj8
Severity HIGH
CVSS v3.1 Base Score N/A
CWE Classification CWE-407: Inefficient Algorithmic Complexity
Affected Product parse-server
Package Ecosystem npm
Published Date
Last Updated

How to Fix GHSA-cgxm-vr2f-6fj8

To remediate this vulnerability, upgrade all affected parse-server dependencies to a patched release. Both direct and transitive dependencies should be checked, as frameworks or security libraries may pull in vulnerable versions transitively.

parse-server fixed: 9.9.1-alpha.12 
npm install parse-server@9.9.1-alpha.12
parse-server fixed: 8.6.82 
npm install parse-server@8.6.82
Verify Direct and Transitive Dependencies

Run the following command in your project directory to verify that all resolved dependencies use the patched release: 

npm ls parse-server

How to Check if You Are Affected

To determine whether your Node.js application is affected by GHSA-cgxm-vr2f-6fj8, inspect your project dependencies using npm:

npm ls parse-server

Analyze the terminal output to locate any version of parse-server in your dependency tree. If any resolved version matches the vulnerable ranges listed in the table below (for example, versions earlier than 9.9.1-alpha.12), your application is affected.

Note: The npm ls parse-server command inspects dependencies declared in your package.json and lockfile; it does not perform automated runtime dynamic scanning.

Technical Details

Vulnerability Mechanism & Technical Analysis

This vulnerability is classified under CWE-407: Inefficient Algorithmic Complexity, where an algorithm in a product has an inefficient worst-case computational complexity that may be detrimental to system performance and can be triggered by an attacker, typically using crafted manipulations that ensure that the worst case is being reached. In parse-server, software state validation or input boundaries are circumvented during processing. Review the official source advisory statement below for specific affected components, classes, and reproduction details.

Source Advisory Statement

### Impact Parse Server is vulnerable to denial of service. A remote attacker can send a single, small query (~1 KB) containing deeply nested query condition operators. Parse Server processes the nested structure with exponential time complexity, which blocks the Node.js event loop and makes the server unresponsive to all clients for the duration of processing. A single request can occupy the event loop for many seconds, and the request is repeatable. The issue affects the REST API and LiveQuery query handling and is reachable in the default configuration. Exploitation requires only the public application identifier; no user authentication is needed. ### Patches The internal query-traversal helper that previously re-walked nested arrays — causing exponential-time processing of nested `$or`/`$and`/`$nor` operators — was corrected to traverse queries in linear time. Additionally, the optional `requestComplexity.queryDepth` limit was generalized so that nested logical operators are counted even when wrapped inside field-level operators (e.g. `$elemMatch`, `$not`) or plain field names, closing a bypass of the limit on both the REST API and LiveQuery. ### Workarounds There is no complete configuration-only workaround on affected versions. Setting `requestComplexity.queryDepth` to a small positive integer reduces exposure but does not fully prevent the issue, because the limit can be bypassed by nesting the operators inside a field-level operator. Upgrading is strongly recommended.

GHSA-cgxm-vr2f-6fj8 Affected parse-server Versions

2 component(s)
Fixed Versions:
9.9.1-alpha.128.6.82
Product / Package Ecosystem Affected Versions Fixed Version
parse-server
npm/parse-server
npm
≥ 9.0.0
< 9.9.1-alpha.12
9.9.1-alpha.12
parse-server
npm/parse-server
npm
< 8.6.82
8.6.82

References

GitHub Advisory / Wiki ADVISORY
https://github.com/parse-community/parse-server/security/advisories/GHSA-cgxm-vr2f-6fj8
parse-server Source Repository REPOSITORY
https://github.com/parse-community/parse-server/pull/10511
parse-server Source Repository REPOSITORY
https://github.com/parse-community/parse-server/pull/10512
parse-server Source Repository REPOSITORY
https://github.com/parse-community/parse-server

Frequently Asked Questions

What is GHSA-cgxm-vr2f-6fj8?
GHSA-cgxm-vr2f-6fj8 is a security vulnerability in parse-server involving Denial of service via exponential-time processing of deeply nested query operators under CWE-407: Inefficient Algorithmic Complexity.
Which parse-server versions are affected?
Affected versions include releases prior to 9.9.1-alpha.12, 8.6.82 across affected packages: parse-server.
What version fixes GHSA-cgxm-vr2f-6fj8?
Upgrading to 9.9.1-alpha.12, 8.6.82 (or the latest patched release for your respective branch) resolves the vulnerability.
Is parse-server affected?
Yes, parse-server is affected in releases prior to 9.9.1-alpha.12, 8.6.82. Upgrade your dependency to 9.9.1-alpha.12, 8.6.82 or later.
What CWE is associated with GHSA-cgxm-vr2f-6fj8?
GHSA-cgxm-vr2f-6fj8 is classified under CWE-407: Inefficient Algorithmic Complexity (An algorithm in a product has an inefficient worst-case computational complexity that may be detrimental to system performance and can be triggered by an attacker, typically using crafted manipulations that ensure that the worst case is being reached.).
How can I check npm dependencies for GHSA-cgxm-vr2f-6fj8?
Run the dependency tree command: 'npm ls parse-server'. This command lists direct and transitive dependencies in your build configuration so you can verify if a vulnerable version is resolved.
Machine-readable OSV JSON OSV v1.5 Schema
Normalized schema output
View Raw JSON 
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  "id" : "GHSA-cgxm-vr2f-6fj8",
  "modified" : "2026-06-19T14:50:14Z",
  "published" : "2026-06-19T14:50:14Z",
  "aliases" : [ ],
  "summary" : "parse-server: Denial of service via exponential-time processing of deeply nested query operators",
  "details" : "### Impact\n\nParse Server is vulnerable to denial of service. A remote attacker can send a single, small query (~1 KB) containing deeply nested query condition operators. Parse Server processes the nested structure with exponential time complexity, which blocks the Node.js event loop and makes the server unresponsive to all clients for the duration of processing. A single request can occupy the event loop for many seconds, and the request is repeatable. The issue affects the REST API and LiveQuery query handling and is reachable in the default configuration. Exploitation requires only the public application identifier; no user authentication is needed.\n\n### Patches\n\nThe internal query-traversal helper that previously re-walked nested arrays — causing exponential-time processing of nested `$or`/`$and`/`$nor` operators — was corrected to traverse queries in linear time. Additionally, the optional `requestComplexity.queryDepth` limit was generalized so that nested logical operators are counted even when wrapped inside field-level operators (e.g. `$elemMatch`, `$not`) or plain field names, closing a bypass of the limit on both the REST API and LiveQuery.\n\n### Workarounds\n\nThere is no complete configuration-only workaround on affected versions. Setting `requestComplexity.queryDepth` to a small positive integer reduces exposure but does not fully prevent the issue, because the limit can be bypassed by nesting the operators inside a field-level operator. Upgrading is strongly recommended.",
  "severity" : [ {
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}