Description
When a post is published, Postiz treats a media path that is not a web address as a file on the server's disk, but it does not check that the file lies inside the upload directory. A registered user can store a crafted media path with a post, get it past the checks that normally restrict it, and have the publishing worker read an arbitrary file and send it as an attachment to a Discord server the user controls. The same unconfined reads can be reached through two further routes. One tells the caller whether a file exists and can exhaust the backend's memory, the other delivers the file the same way as the main route. Self-registration is open by default, so the attacker needs no existing account.
References4
Metrics
- CVSS 3.1
-
9.6
CRITICAL
Score source: CNA
CVSS:3.1/AV:N/AC:L/PR:L/UI:N/S:C/C:H/I:H/A:N - EPSS — exploit probability
- 0% percentile: 37 · as of 8 November 2026
- CWE
- CWE-22CWE-74
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