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.
Fix
Nothing published yet: no patch, vendor advisory or mitigation reference on NVD, no vendor advisory in the News for this CVE, not in CISA's KEV, no fixed package version. BaselineWatch does not guess at one.
Change history 1
- First seenCVSS 5.9NVD modified 2026-10-26 14:10
Affected (CPE criteria) 0
NVD has not attached CPE configurations yet.
References 10
- https://github.com/python/cpython/commit/2bbcf3fb7a420a05605576c0f9468d4675381b5f
- https://github.com/python/cpython/commit/5dadc64673ce875ebfb24163907777dae0f6ca06
- https://github.com/python/cpython/commit/7d95a1dc7382b55cba7fdd6a110336077584a4f0
- https://github.com/python/cpython/commit/bb3446dda6c49b32e67c11dbbbf221b40be00763
- https://github.com/python/cpython/commit/c88704431ea3248ca769384c13856330976fac1d
- https://github.com/python/cpython/commit/eac4fe3b2c77693790a5ef7dfab127c1fee81bf9
- https://github.com/python/cpython/commit/ef12d0dc824baccf737bba1458e5eed3d1e0fceb
- https://github.com/python/cpython/issues/87451
- https://github.com/python/cpython/pull/149648
- https://mail.python.org/archives/list/[email protected]/thread/ITF2BAPBQEPYK3LDMPRSY435JGNHYNDP/