CVE-2026-8328
FTP PASV SSRF, ftpcp() does not use actual peer address, trusts server-supplied PASV host address
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Description
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.
Affected
Our own answer: ranges merged, affected separated from platform-only, with confidence and review flags.
Remediation
No guide yetNo remediation guidance has been written for this CVE yet. What the record does show:
Patch and advisory references
- https://github.com/python/cpython/pull/149648
- https://mail.python.org/archives/list/[email protected]/thread/ITF2BAPBQEPYK3LDMPRSY435JGNHYNDP/
- https://github.com/python/cpython/commit/5dadc64673ce875ebfb24163907777dae0f6ca06
- https://github.com/python/cpython/commit/7d95a1dc7382b55cba7fdd6a110336077584a4f0
- https://github.com/python/cpython/commit/bb3446dda6c49b32e67c11dbbbf221b40be00763
References (10)
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