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.
Weakness
The web server receives a URL or similar request from an upstream component and retrieves the contents of this URL, but it does not sufficiently ensure that the request is being sent to the expected destination.
Affected Software
| Name | Vendor | Start Version | End Version |
|---|---|---|---|
| Python3.13 | Ubuntu | upstream | * |
| Python3.14 | Ubuntu | devel | * |
| Python3.14 | Ubuntu | upstream | * |
Related Attack Patterns
References
- 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/issues/87451
- https://github.com/python/cpython/pull/149648
- https://mail.python.org/archives/list/security-announce@python.org/thread/ITF2BAPBQEPYK3LDMPRSY435JGNHYNDP/