[pyftpdlib] Concurrent Execution using Shared Resource with Improper Synchronization (‘Race Condition’) in pyftpdlib

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
• https://github.com/advisories/GHSA-62xg-239j-vxg7