CVE-2026-29182: Parse Server: Cloud Hooks and Cloud Jobs bypass `readOnlyMasterKey` write restriction
Impact
Parse Server's readOnlyMasterKey option allows access with master-level read privileges but is documented to deny all write operations. However, some endpoints incorrectly accept the readOnlyMasterKey for mutating operations. This allows a caller who only holds the readOnlyMasterKey to create, modify, and delete Cloud Hooks and to start Cloud Jobs, which can be used for data exfiltration.
Any Parse Server deployment that uses the readOnlyMasterKey option is affected. Note than an attacker needs to know the readOnlyMasterKey to exploit this vulnerability.
Patches
The fix adds authorization checks, rejecting mutating requests made with the readOnlyMasterKey.
Workarounds
There is no known workaround other than upgrading. If upgrading is not immediately possible, ensure the readOnlyMasterKey value is not shared with untrusted parties.
Resources
- GitHub security advisory: https://github.com/parse-community/parse-server/security/advisories/GHSA-vc89-5g3r-cmhh - Fixed in Parse Server 9.4.1-alpha.3: https://github.com/parse-community/parse-server/releases/tag/9.4.1-alpha.3 - Fixed in Parse Server 8.6.4: https://github.com/parse-community/parse-server/releases/tag/8.6.4
Other sources
Parse Server is an open source backend that can be deployed to any infrastructure that can run Node.js. Prior to versions 8.6.4 and 9.4.1-alpha.3, Parse Server's readOnlyMasterKey option allows access with master-level read privileges but is documented to deny all write operations. However, some endpoints incorrectly accept the readOnlyMasterKey for mutating operations. This allows a caller who only holds the readOnlyMasterKey to create, modify, and delete Cloud Hooks and to start Cloud Jobs, which can be used for data exfiltration. Any Parse Server deployment that uses the readOnlyMasterKey option is affected. Note than an attacker needs to know the readOnlyMasterKey to exploit this vulnerability. This issue has been patched in versions 8.6.4 and 9.4.1-alpha.3.
— MITRE
Affected Software
Remediation
Event History
Frequently Asked Questions
What is the severity of CVE-2026-29182?
CVE-2026-29182 is considered a critical vulnerability due to its potential to allow unauthorized write access to the database.
How do I fix CVE-2026-29182?
To fix CVE-2026-29182, upgrade to Parse Server version 8.6.4 or 9.4.1-alpha.3 or later.
What is the impact of CVE-2026-29182?
CVE-2026-29182 allows unauthorized users holding a read-only master key to execute write operations on the affected endpoints.
Which versions of Parse Server are affected by CVE-2026-29182?
Versions of Parse Server from prior to 8.6.4 and between 9.0.0 and 9.4.1-alpha.2 are affected by CVE-2026-29182.
Is CVE-2026-29182 a known issue with Parse Server?
Yes, CVE-2026-29182 is documented in the Parse Server advisory and has been acknowledged by the development community.