Fetchmail versions prior to 5.9.10 have a buffer overflow vulnerability
that may be exploited by a malicious IMAP server.
The fetchmail client allocated memory to store the sizes of the
messages it is attempting to retrieve based on
a message count provided by the IMAP server.
A malicious IMAP server could provide an artifically
large message count to force the
fetchmail process to write data outside of the allocated memory. (First LWN
report: May 9).
