Description
Monsta FTP before 2.14.5 contains a server-side request forgery vulnerability in the fetchRemoteFile action caused by an incomplete IP blocklist check in the isBlockedIP() function, which fails to detect embedded IPv4 addresses within IPv4-mapped IPv6 addresses. An unauthenticated attacker can obtain a CSRF token from the public getSystemVars endpoint and submit a fetchRemoteFile request with a source URL resolving to an IPv4-mapped address, causing the server to issue HTTP requests to internal services and write responses to an attacker-controlled FTP destination, enabling retrieval of cloud instance metadata credentials.
CVSS 8.6EPSS 0.47400000000000003%Risk 0.9
View source- Published
- 2026-07-08 21:16:54
- Affected versions
- <2.14.5
- Type
- Critical software
- Vector
- CVSS:3.1/AV:N/AC:L/PR:N/UI:N/S:C/C:H/I:N/A:N