Description
ownCloud Guests before 0.12.5 allows unauthenticated user enumeration via the /apps/guests/register/{email}/{token} endpoint. Because of insufficient validation of the supplied token in showPasswordForm, the server responds differently when an e-mail address corresponds to a valid pending guest user rather than a non-existent user.
Affected products
owncloud: guests
References4
- gist.github.com/thesmartshadow/64ae0449e909174d0479a4f23657147f ExploitThird Party Advisory
- github.com/owncloud/guests Product
- marketplace.owncloud.com/apps/guests Product
- yeswehack.com/reports/411806 Permissions Required
Metrics
- CVSS 3.1
-
5.3
MEDIUM
Score source: CNA
CVSS:3.1/AV:N/AC:L/PR:N/UI:N/S:U/C:L/I:N/A:N - EPSS — exploit probability
- 1% percentile: 62 · as of 10 November 2026
- CWE
- CWE-200CWE-203
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