Race condition in the FTPHandler class in ftpserver.py in pyftpdlib before 0.5.2 allows remote attackers to cause a denial of service (daemon outage) by establishing and then immediately closing a TCP connection, leading to the getpeername function having an ENOTCONN error, a different vulnerability than CVE-2010-3494.

References

• https://nvd.nist.gov/vuln/detail/CVE-2009-5011
• http://code.google.com/p/pyftpdlib/issues/detail?id=100
• GHSA-62xg-239j-vxg7
• https://github.com/pypa/advisory-database/tree/main/vulns/pyftpdlib/PYSEC-2010-8.yaml
• http://code.google.com/p/pyftpdlib/source/browse/trunk/HISTORY
• http://code.google.com/p/pyftpdlib/source/detail?r=543
• http://code.google.com/p/pyftpdlib/source/diff?spec=svn543&r=543&format=side&path=/trunk/pyftpdlib/ftpserver.py