CVE-2026-8328 (GCVE-0-2026-8328)

Vulnerability from cvelistv5 – Published: 2026-05-13 20:14 – Updated: 2026-05-14 12:49
VLAI?
Title
FTP PASV SSRF, ftpcp() does not use actual peer address, trusts server-supplied PASV host address
Summary
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.
Severity ?
5.9 (Medium)
CVSS:4.0/AV:N/AC:L/AT:P/PR:N/UI:A/VC:N/VI:H/VA:N/SC:N/SI:N/SA:N
CWE
  • CWE-918 - Server-Side request forgery (SSRF)
Assigner
PSF
References
Impacted products
Vendor Product Version
Python Software Foundation CPython Affected: 0 , < 3.15.0 (python)
Create a notification for this product.
Credits
Qi Deng (https://github.com/ikow) Bénédikt Tran (https://github.com/picnixz) Gregory P. Smith (https://github.com/gpshead)
Show details on NVD website
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Forecast uses a logistic model when the trend is rising, or an exponential decay model when the trend is falling. Fitted via linearized least squares.

Sightings

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Nomenclature

  • Seen: The vulnerability was mentioned, discussed, or observed by the user.
  • Confirmed: The vulnerability has been validated from an analyst's perspective.
  • Published Proof of Concept: A public proof of concept is available for this vulnerability.
  • Exploited: The vulnerability was observed as exploited by the user who reported the sighting.
  • Patched: The vulnerability was observed as successfully patched by the user who reported the sighting.
  • Not exploited: The vulnerability was not observed as exploited by the user who reported the sighting.
  • Not confirmed: The user expressed doubt about the validity of the vulnerability.
  • Not patched: The vulnerability was not observed as successfully patched by the user who reported the sighting.



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