CVE-2026-8328 MEDIUM

CVE-2026-8328: FTP PASV SSRF, ftpcp() does not use actual peer address, trusts server-supplied PASV host address

Vendor Python Software Foundation
Product CPython
Weakness CWE-918 · SSRF
Published May 13, 2026
Last update June 30, 2026
View on NVD All CVEs

CVSS base score

5.9/10
Attack vector Network
Attack complexity Low
Privileges required None
User interaction —
Confidentiality —
Integrity —

CVSS vector

CVSS:4.0/AV:N/AC:L/AT:P/PR:N/UI:A/VC:N/VI:H/VA:N/SC:N/SI:N/SA:N

What the vulnerability does

01Description

The ftpcp() function in Lib/ftplib.py was not updated when CVE-2021-4189 was fixed. While makepasv() was patched to replace server-supplied PASV host addresses with the actual peer address (getpeername()[0]), ftpcp() still calls parse227() directly and passes the raw attacker-controllable IP address and port to target.sendport(). This patch is related to CVE-2021-4189.

Key dates

02Disclosure timeline

May 13, 2026 CVE published
June 30, 2026 Record updated