Parse Server is an open source backend that can be deployed to any infrastructure that can run Node.js. Prior to versions 8.6.54 and 9.6.0-alpha.43, an attacker can subscribe to LiveQuery with a watch parameter targeting a protected field. Although the protected field value is properly stripped from event payloads, the presence or absence of update events reveals whether the protected field changed, creating a binary oracle. For boolean protected fields, the timing of change events is equivalent to knowing the field value. This issue has been patched in versions 8.6.54 and 9.6.0-alpha.43.
https://github.com/parse-community/parse-server/security/advisories/GHSA-qpc3-fg4j-8hgm
https://github.com/parse-community/parse-server/pull/10254
https://github.com/parse-community/parse-server/pull/10253
https://github.com/parse-community/parse-server/commit/c62eacaf38de86913f09240583448360b1cc8e67
https://github.com/parse-community/parse-server/commit/0c0a0a5a37ca821d2553119f2cb3be35322eda4b
Published: 2026-03-24
Updated: 2026-03-25
Base Score: 5
Vector: CVSS2#AV:N/AC:L/Au:N/C:P/I:N/A:N
Severity: Medium
Base Score: 5.3
Vector: CVSS:3.1/AV:N/AC:L/PR:N/UI:N/S:U/C:L/I:N/A:N
Severity: Medium
Base Score: 6.3
Vector: CVSS:4.0/AV:N/AC:L/AT:P/PR:N/UI:N/VC:L/VI:N/VA:N/SC:N/SI:N/SA:N
Severity: Medium
EPSS: 0.00045