Description
Postiz is an AI social media scheduling tool. Prior to version 2.21.3, the POST /public/v1/upload-from-url endpoint accepts a user-supplied URL and fetches it server-side using axios.get() with no SSRF protections. The only validation is a file extension check (.png, .jpg, etc.) which is trivially bypassed by appending an image extension to any URL path. An authenticated API user can fetch internal network resources, cloud instance metadata, and other internal services, with the response data uploaded to storage and returned to the attacker. This issue has been patched in version 2.21.3.
CVSS breakdown
CVSS 4.0
Attack Vector
Network
Attack Complexity
Low
Attack Requirements
None
Privileges Required
Low
User Interaction
None
Confidentiality (Vulnerable System)
High
Integrity (Vulnerable System)
None
Availability (Vulnerable System)
None
Confidentiality (Subsequent System)
High
Integrity (Subsequent System)
None
Availability (Subsequent System)
None
Affected products
- gitroomhq / postiz-app< 2.21.3 – < 2.21.3