Parse Server is an open source backend that can be deployed to any infrastructure that can run Node.js. Prior o 9.5.2-alpha.10 and 8.6.23, Parse Server's rate limiting middleware is applied at the Express middleware layer, but the batch request endpoint (/batch) processes sub-requests internally by routing them directly through the Promise router, bypassing Express middleware including rate limiting. An attacker can bundle multiple requests targeting a rate-limited endpoint into a single batch request to circumvent the configured rate limit. Any Parse Server deployment that relies on the built-in rate limiting feature is affected. This vulnerability is fixed in 9.5.2-alpha.10 and 8.6.23.
https://github.com/parse-community/parse-server/security/advisories/GHSA-775h-3xrc-c228
https://github.com/parse-community/parse-server/releases/tag/9.5.2-alpha.10
https://github.com/parse-community/parse-server/releases/tag/8.6.23
Published: 2026-03-10
Updated: 2026-03-11
Base Score: 7.8
Vector: CVSS2#AV:N/AC:L/Au:N/C:N/I:N/A:C
Severity: High
Base Score: 7.5
Vector: CVSS:3.1/AV:N/AC:L/PR:N/UI:N/S:U/C:N/I:N/A:H
Severity: High
Base Score: 6.9
Vector: CVSS:4.0/AV:N/AC:L/AT:N/PR:N/UI:N/VC:N/VI:N/VA:N/SC:N/SI:N/SA:L
Severity: Medium
EPSS: 0.0004