Monsta FTP < 2.14.5 SSRF via IPv4-Mapped IPv6 Address Bypass
78Vexday Risk Score
Patch now. It exploitation observed by VulnCheck and has a working public exploit.
ssvc Actcvss 7.7epss 1.5%
from disclosure to weapon
Published on NVDJul 8
VulnCheck+61d
exploitation probability
1.5%top 27% of all CVEs
observed exploitation
yesVulnCheck
1 public exploit(s)
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:4.0/AV:N/AC:L/AT:N/PR:N/UI:N/VC:N/VI:N/VA:N/SC:H/SI:N/SA:N
Affected products
Monsta Limited of New Zealand · Monsta FTPpublic PoCs found — 1
cve_referencewww.vulncheck.com/blog/monsta-ftp-ssrf-ipv6-blocklist-bypassunverified⚠ Public resources, to assess the exposure of systems you control or are authorized to test. Test only with authorization.