A company spokesman said full details would be released only after a three-month period, to give users time to download a version of the mail client in which the bugs have been fixed.
According to the advisory, here, Qualcomm, which makes Eudora, has released version 6.2.1 which addresses these problems.
The flaw creates errors in the viewing of emails and the handling of stationery and mailbox files.
A successful exploit will permit an attacker to execute code with the privileges of the user running Eudora. µ