[3.15] gh-87451: Apply CVE-2021-4189 PASV fix to ftplib.ftpcp() (GH-149648)#149792
Open
miss-islington wants to merge 1 commit into
Open
[3.15] gh-87451: Apply CVE-2021-4189 PASV fix to ftplib.ftpcp() (GH-149648)#149792miss-islington wants to merge 1 commit into
miss-islington wants to merge 1 commit into
Conversation
…nGH-149648) ftpcp() called parse227() directly and passed the source server's self-reported PASV IPv4 address to the target server's PORT command, bypassing the CVE-2021-4189 fix that was applied only to FTP.makepasv(). A malicious source FTP server could use this to redirect the target server's data connection to an arbitrary host:port (SSRF). ftpcp() now uses the source server's actual peer address, honoring the existing trust_server_pasv_ipv4_address opt-out, the same as makepasv(). Thanks to Qi Ding at Aurascape AI for the report. (GHSA-w8c5-q2xf-gf7c) (cherry picked from commit eac4fe3) Co-authored-by: Gregory P. Smith <[email protected]>
This was referenced May 13, 2026
This file contains hidden or bidirectional Unicode text that may be interpreted or compiled differently than what appears below. To review, open the file in an editor that reveals hidden Unicode characters.
Learn more about bidirectional Unicode characters
Sign up for free
to join this conversation on GitHub.
Already have an account?
Sign in to comment
2 participants
Add this suggestion to a batch that can be applied as a single commit.This suggestion is invalid because no changes were made to the code.Suggestions cannot be applied while the pull request is closed.Suggestions cannot be applied while viewing a subset of changes.Only one suggestion per line can be applied in a batch.Add this suggestion to a batch that can be applied as a single commit.Applying suggestions on deleted lines is not supported.You must change the existing code in this line in order to create a valid suggestion.Outdated suggestions cannot be applied.This suggestion has been applied or marked resolved.Suggestions cannot be applied from pending reviews.Suggestions cannot be applied on multi-line comments.Suggestions cannot be applied while the pull request is queued to merge.Suggestion cannot be applied right now. Please check back later.
ftpcp() called parse227() directly and passed the source server's
self-reported PASV IPv4 address to the target server's PORT command,
bypassing the CVE-2021-4189 fix that was applied only to FTP.makepasv().
A malicious source FTP server could use this to redirect the target
server's data connection to an arbitrary host:port (SSRF).
ftpcp() now uses the source server's actual peer address, honoring the
existing trust_server_pasv_ipv4_address opt-out, the same as makepasv().
Thanks to Qi Ding at Aurascape AI for the report. (GHSA-w8c5-q2xf-gf7c)
(cherry picked from commit eac4fe3)
Co-authored-by: Gregory P. Smith [email protected]