CVE-2026-8328
Medium
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.
SeverityMedium
CVSS5.9
Exploit probability—
ProductCPython
PublishedMay 13, 2026
First seenMay 13, 2026
Weakness typeCWE-918Server-side request forgery (SSRF)
How to fix
Update
- Python Software Foundation CPython3.10.21, 3.11.16, 3.12.14, 3.13.14, 3.14.6, 3.15.0b2 or later
Patches
- github.com/python/cpython/pull/149648
- github.com/python/cpython/commit/5dadc64673ce875ebfb24163907777dae0f6ca06
- github.com/python/cpython/commit/7d95a1dc7382b55cba7fdd6a110336077584a4f0
- github.com/python/cpython/commit/bb3446dda6c49b32e67c11dbbbf221b40be00763
- github.com/python/cpython/commit/c88704431ea3248ca769384c13856330976fac1d
- github.com/python/cpython/commit/eac4fe3b2c77693790a5ef7dfab127c1fee81bf9
- github.com/python/cpython/commit/2bbcf3fb7a420a05605576c0f9468d4675381b5f
- github.com/python/cpython/commit/ef12d0dc824baccf737bba1458e5eed3d1e0fceb
Affected products
| Product | Affected versions | Fixed in |
|---|---|---|
| Python Software Foundation CPython | v < 3.10.21, 3.11.0 ≤ v < 3.11.16, 3.12.0 ≤ v < 3.12.14, 3.13.0 ≤ v < 3.13.14, 3.14.0 ≤ v < 3.14.6, 3.15.0a1 ≤ v < 3.15.0b2 | 3.10.21, 3.11.16, 3.12.14, 3.13.14, 3.14.6, 3.15.0b2 |
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