CVE-2026-33508
Parse Server: LiveQuery subscription query depth bypass
Parse Server is an open source backend that can be deployed to any infrastructure that can run Node.js. Prior to versions 8.6.56 and 9.6.0-alpha.45, Parse Server's LiveQuery component does not enforce the requestComplexity.queryDepth configuration setting when processing WebSocket subscription requests. An attacker can send a subscription with deeply nested logical operators, causing excessive recursion and CPU consumption that degrades or disrupts service availability. This issue has been patched in versions 8.6.56 and 9.6.0-alpha.45.
Attack profile
How easy it is to exploit
- Attack vector
- Network
- Complexity
- Low
- Privileges needed
- None
- User interaction
- None
What an attacker can affect
- Confidentiality
- None
- Integrity
- None
- Availability
- High
Exploit likelihood
What each source reports
CVE List Score used
Parse Server: LiveQuery subscription query depth bypass
Parse Server is an open source backend that can be deployed to any infrastructure that can run Node.js. Prior to versions 8.6.56 and 9.6.0-alpha.45, Parse Server's LiveQuery component does not enforce the requestComplexity.queryDepth configuration setting when processing WebSocket subscription requests. An attacker can send a subscription with deeply nested logical operators, causing excessive recursion and CPU consumption that degrades or disrupts service availability. This issue has been patched in versions 8.6.56 and 9.6.0-alpha.45.
- Record
CVE-2026-33508- CVSS 4.0
- 8.2 High
CVSS:4.0/AV:N/AC:L/AT:P/PR:N/UI:N/VC:N/VI:N/VA:H/SC:N/SI:N/SA:N - Weakness
- CWE-674
- Updated
- 2026-11-02
EUVDEUVD-2026-20071
Parse Server is an open source backend that can be deployed to any infrastructure that can run Node.js. Prior to versions 8.6.56 and 9.6.0-alpha.45, Parse Server's LiveQuery component does not enforce the requestComplexity.queryDepth configuration setting when processing WebSocket subscription requests. An attacker can send a subscription with deeply nested logical operators, causing excessive recursion and CPU consumption that degrades or disrupts service availability. This issue has been patched in versions 8.6.56 and 9.6.0-alpha.45.
- Record
EUVD-2026-20071- CVSS 4.0
- 8.2 High
CVSS:4.0/AV:N/AC:L/AT:P/PR:N/UI:N/VC:N/VI:N/VA:H/SC:N/SI:N/SA:N - Updated
- 2026-11-02
GitHub AdvisoriesGHSA-6qh5-m6g3-xhq6
Parse Server LiveQuery subscription query depth bypass
Impact
Parse Server's LiveQuery component does not enforce the requestComplexity.queryDepth configuration setting when processing WebSocket subscription requests. An attacker can send a subscription with deeply nested logical operators, causing excessive recursion and CPU consumption that degrades or disrupts service availability.
Deployments are affected when the LiveQuery WebSocket endpoint is reachable by untrusted clients.
Patches
The fix adds query condition depth validation to the LiveQuery subscription handler, enforcing the same requestComplexity.queryDepth limit that already protects REST API queries.
Workarounds
There is no known workaround other than upgrading.
- Record
GHSA-6qh5-m6g3-xhq6- CVSS 4.0
- 8.2 High
CVSS:4.0/AV:N/AC:L/AT:P/PR:N/UI:N/VC:N/VI:N/VA:H/SC:N/SI:N/SA:N - CVSS 3.1
- 7.5 High
CVSS:3.1/AV:N/AC:L/PR:N/UI:N/S:U/C:N/I:N/A:H - Weakness
- CWE-674
- Updated
- 2026-11-02
NVD
Parse Server is an open source backend that can be deployed to any infrastructure that can run Node.js. Prior to versions 8.6.56 and 9.6.0-alpha.45, Parse Server's LiveQuery component does not enforce the requestComplexity.queryDepth configuration setting when processing WebSocket subscription requests. An attacker can send a subscription with deeply nested logical operators, causing excessive recursion and CPU consumption that degrades or disrupts service availability. This issue has been patched in versions 8.6.56 and 9.6.0-alpha.45.
- Record
CVE-2026-33508- CVSS 4.0
- 8.2 High
CVSS:4.0/AV:N/AC:L/AT:P/PR:N/UI:N/VC:N/VI:N/VA:H/SC:N/SI:N/SA:N/E:X/CR:X/IR:X/AR:X/MAV:X/MAC:X/MAT:X/MPR:X/MUI:X/MVC:X/MVI:X/MVA:X/MSC:X/MSI:X/MSA:X/S:X/AU:X/R:X/V:X/RE:X/U:X - CVSS 3.1
- 7.5 High
CVSS:3.1/AV:N/AC:L/PR:N/UI:N/S:U/C:N/I:N/A:H - Weakness
- CWE-674
- Updated
- 2026-11-02
OSV
Parse Server: LiveQuery subscription query depth bypass
Parse Server is an open source backend that can be deployed to any infrastructure that can run Node.js. Prior to versions 8.6.56 and 9.6.0-alpha.45, Parse Server's LiveQuery component does not enforce the requestComplexity.queryDepth configuration setting when processing WebSocket subscription requests. An attacker can send a subscription with deeply nested logical operators, causing excessive recursion and CPU consumption that degrades or disrupts service availability. This issue has been patched in versions 8.6.56 and 9.6.0-alpha.45.
- Record
CVE-2026-33508- CVSS 4.0
- 8.2 High
CVSS:4.0/AV:N/AC:L/AT:P/PR:N/UI:N/VC:N/VI:N/VA:H/SC:N/SI:N/SA:N - Weakness
- CWE-674
- Updated
- 2026-11-02
OSVGHSA-6qh5-m6g3-xhq6
Parse Server LiveQuery subscription query depth bypass
Impact
Parse Server's LiveQuery component does not enforce the requestComplexity.queryDepth configuration setting when processing WebSocket subscription requests. An attacker can send a subscription with deeply nested logical operators, causing excessive recursion and CPU consumption that degrades or disrupts service availability.
Deployments are affected when the LiveQuery WebSocket endpoint is reachable by untrusted clients.
Patches
The fix adds query condition depth validation to the LiveQuery subscription handler, enforcing the same requestComplexity.queryDepth limit that already protects REST API queries.
Workarounds
There is no known workaround other than upgrading.
- Record
GHSA-6qh5-m6g3-xhq6- CVSS 4.0
- 8.2 High
CVSS:4.0/AV:N/AC:L/AT:P/PR:N/UI:N/VC:N/VI:N/VA:H/SC:N/SI:N/SA:N - CVSS 3.1
- 7.5 High
CVSS:3.1/AV:N/AC:L/PR:N/UI:N/S:U/C:N/I:N/A:H - Weakness
- CWE-674
- Updated
- 2026-11-02
OSVBIT-parse-2026-33508 No score
Parse Server: LiveQuery subscription query depth bypass
Parse Server is an open source backend that can be deployed to any infrastructure that can run Node.js. Prior to versions 8.6.56 and 9.6.0, Parse Server's LiveQuery component does not enforce the requestComplexity.queryDepth configuration setting when processing WebSocket subscription requests. An attacker can send a subscription with deeply nested logical operators, causing excessive recursion and CPU consumption that degrades or disrupts service availability. This issue has been patched in versions 8.6.56 and 9.6.0
- Record
BIT-parse-2026-33508- Updated
- 2026-11-02
Affected products
Affected packages
| Package | Affected | Fixed |
|---|---|---|
parse-servernpm |
9.0.0 up to 9.6.0-alpha.45 | 9.6.0-alpha.45 |
parse-servernpm |
before 8.6.56 | 8.6.56 |
parseBitnami |
before 8.6.56, 9.0.0 up to 9.6.0 | 8.6.569.6.0 |
History
| Recorded | Changed | Sources |
|---|---|---|
| first indexed | CVE List, EUVD, GitHub Advisories, NVD, OSV |
Dates are when Every CVE recorded each change. Upstream dates may differ.
In short
CVE-2026-33508 is a high vulnerability (CVSS 8.2) in Parse-community Parse-server, published March 20, 2026. No source lists public exploit code. EPSS puts the chance of exploitation in the next 30 days at 0.35%, the 29th percentile. Fixed in parse-server 9.6.0-alpha.45.
References
github.com/parse-community/parse-server/security/advisories/GHSA-6qh5-m6g3-xhq6
nvd.nist.gov/vuln/detail/CVE-2026-33508