Parse Server is an open source backend that can be deployed to any infrastructure that can run Node.js. Prior to versions 8.6.51 and 9.6.0-alpha.40, the Pages route and legacy PublicAPI route for resending email verification links return distinguishable responses depending on whether the provided username exists and has an unverified email. This allows an unauthenticated attacker to enumerate valid usernames by observing different redirect targets. The existing emailVerifySuccessOnInvalidEmail configuration option, which is enabled by default and protects the API route against this, did not apply to these routes. This issue has been patched in versions 8.6.51 and 9.6.0-alpha.40.
PUBLISHED5.2CWE-204
Parse Server: Email verification resend page leaks user existence
Problem type
Affected products
parse-community
parse-server
< 8.6.51 - AFFECTED
>= 9.0.0, < 9.6.0-alpha.40 - AFFECTED
References
https://github.com/parse-community/parse-server/security/advisories/GHSA-h29g-q5c2-9h4f
https://github.com/parse-community/parse-server/security/advisories/GHSA-h29g-q5c2-9h4f
https://github.com/parse-community/parse-server/pull/10238
https://github.com/parse-community/parse-server/pull/10238
https://github.com/parse-community/parse-server/pull/10243
https://github.com/parse-community/parse-server/pull/10243
https://github.com/parse-community/parse-server/commit/967aa57732202009b2389ce9ecb3130d53d657e5
https://github.com/parse-community/parse-server/commit/967aa57732202009b2389ce9ecb3130d53d657e5
https://github.com/parse-community/parse-server/commit/fbda4cb0c5cbc8fad08a216823b6b64d4ae289c3
https://github.com/parse-community/parse-server/commit/fbda4cb0c5cbc8fad08a216823b6b64d4ae289c3
GitHub Security Advisories
GHSA-h29g-q5c2-9h4f
Parse Server email verification resend page leaks user existence
https://github.com/advisories/GHSA-h29g-q5c2-9h4fImpact
The Pages route and legacy PublicAPI route for resending email verification links return distinguishable responses depending on whether the provided username exists and has an unverified email. This allows an unauthenticated attacker to enumerate valid usernames by observing different redirect targets. The existing emailVerifySuccessOnInvalidEmail configuration option, which is enabled by default and protects the API route against this, did not apply to these routes.
Patches
The email verification resend routes now respect the emailVerifySuccessOnInvalidEmail option. When set to true (the default), both routes redirect to the success page regardless of the outcome, preventing user enumeration.
Workarounds
There is no known workaround to prevent the information disclosure other than upgrading.
JSON source
https://cveawg.mitre.org/api/cve/CVE-2026-33323Click to expand
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"dateUpdated": "2026-03-24T18:06:32.189Z",
"dateReserved": "2026-03-18T21:23:36.677Z",
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