CVE-2026-8328: Python Software Foundation CPython · Server-Side Request Forgery (SSRF)
Affects Python Software Foundation CPythonSource CVE Database V5
Mentioned vulnerabilities
Not known to be exploited · CVSS 5.9 Medium · fixed in 3.15.0b2 : update Python Software Foundation CPython when convenient.
Data as of 30 Oct 2026, 11:52 UTC
- EPSS
- 0.4% chance of exploitation in 30 days – higher than 39% of CVEsExploit Prediction Scoring System: the likelihood attackers will use this flaw soon.
- Patch
- Available – fixed in 3.15.0b2, 3.14.6, 3.13.14 +3
CVSS:4.0/AV:N/AC:L/AT:P/PR:N/UI:A/VC:N/VI:H/VA:N/SC:N/SI:N/SA:NExploitation evidence
Disclosed: evidence found.
CVE published 13 May 2026
Detectable: no evidence on record.
No public nuclei template indexed
Weaponized: no evidence on record.
No public exploit code indexed in Metasploit or Exploit-DB
Exploited in the wildExploited: no evidence on record.
Not in CISA KEV and no source reports exploitation
Observed by OffSeq MirageSeen by Mirage: no evidence on record.
No attack traffic recorded by OffSeq Mirage sensors
A missing step is not evidence of safety. Sources: cve.org (opens in a new tab), the Metasploit, Exploit-DB and nuclei-templates index as of 30 Oct 2026.
What to do
Upgrade to a fixed release listed under Affected software.
Affected software
| Product | Affected | Fixed in |
|---|---|---|
| Python Software FoundationCPython | Affected
| Fixed in
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| Python Software FoundationCPython | Affected
| Fixed in
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| Python Software FoundationCPython | Affected
| Fixed in
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| Python Software FoundationCPython | Affected
| Fixed in
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| Python Software FoundationCPython | Affected
| Fixed in
|
| Python Software FoundationCPython | Affected
| Fixed in
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Check your own hosts for these packages with threat-finder (opens in a new tab), our free open-source scanner.
AI-suggested
If you cannot patch yet, users should exercise caution when using the ftpcp() function with untrusted FTP servers or inputs.
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.
References
- github.com/python/cpython/issues/87451 (opens in a new tab)
- github.com/python/cpython/pull/149648 (opens in a new tab)
- mail.python.org/archives/list/security-announce@python.org/thread/ITF2BAPBQEPYK3LDMPRSY435JGNHYNDP/ (opens in a new tab)
- github.com/python/cpython/commit/5dadc64673ce875ebfb24163907777dae0f6ca06 (opens in a new tab)
- github.com/python/cpython/commit/7d95a1dc7382b55cba7fdd6a110336077584a4f0 (opens in a new tab)
- github.com/python/cpython/commit/bb3446dda6c49b32e67c11dbbbf221b40be00763 (opens in a new tab)
- github.com/python/cpython/commit/c88704431ea3248ca769384c13856330976fac1d (opens in a new tab)
- github.com/python/cpython/commit/eac4fe3b2c77693790a5ef7dfab127c1fee81bf9 (opens in a new tab)
- github.com/python/cpython/commit/2bbcf3fb7a420a05605576c0f9468d4675381b5f (opens in a new tab)
- github.com/python/cpython/commit/ef12d0dc824baccf737bba1458e5eed3d1e0fceb (opens in a new tab)