GHSA-cgxm-vr2f-6fj8
parse-server: Denial of service via exponential-time processing of deeply nested query operators
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.
Blast Radius
Weekly download volume for affected packages — a proxy for how broadly this vulnerability is deployed.
parse-servernpmDescription
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.
Affected Packages
| Ecosystem | Package | Vulnerable range | Fix |
|---|---|---|---|
| 📦npm | parse-server | ≥ 9.0.0&&< 9.9.1-alpha.12 | 9.9.1-alpha.12 |
| 📦npm | parse-server | all versions | 8.6.82 |
Detection & mitigation playbook
Open-source dependencyDetect
Scan your dependency tree (package-lock.json, pnpm-lock.yaml, requirements.txt, go.sum, etc.) for parse-server. O3's reachability analysis confirms whether the vulnerable code path is actually invoked in your application, so you act on real exposure instead of every transitive match.
Fix
Update parse-server to 9.9.1-alpha.12 or later, then make sure no transitive (indirect) dependency still pins the vulnerable range — O3 confirms GHSA-cgxm-vr2f-6fj8 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 pinpoints whether GHSA-cgxm-vr2f-6fj8 is reachable in your code and exactly where to fix it, then blocks exploitation in production at runtime until the patched version is deployed.
Tailored to GHSA-cgxm-vr2f-6fj8. Runtime protection reduces exposure until a permanent patch is applied and verified — it complements patching, it doesn't replace it.
Frequently Asked Questions
Is GHSA-cgxm-vr2f-6fj8 in your dependencies?
O3 detects GHSA-cgxm-vr2f-6fj8 across npm dependencies and uses function-level reachability to confirm whether the vulnerable code path is actually reachable — not just present. No false positives.