Eudora email client 5.1.1, with "use Microsoft viewer" enabled, allows remote attackers to execute arbitrary programs via an HTML email message containing a META refresh tag that references an embedded .mhtml file with ActiveX controls that execute a second embedded program, which is processed by Internet Explorer.
Eudora 5.1 allows remote attackers to bypass security warnings and possibly execute arbitrary code via attachments with names containing a trailing "." (dot).
Qualcomm Eudora 5.1.1, 5.2, and possibly other versions stores email attachments in a predictable location, which allows remote attackers to read arbitrary files via a link that loads an attachment with malicious script into a frame, which then executes the script in the local browser context.
Buffer overflow in Qpopper (popper) 4.0.4 and earlier allows local users to cause a denial of service and possibly execute arbitrary code via a long bulldir argument in the user's .qpopper-options configuration file.
Qpopper (aka in.qpopper or popper) 4.0.3 and earlier allows remote attackers to cause a denial of service (CPU consumption) via a very large string, which causes an infinite loop.
Eudora 5.1 and earlier versions stores attachments in a directory with a fixed name, which could make it easier for attackers to exploit vulnerabilities in other software that rely on installing and reading files from directories with known pathnames.
Buffer overflow in Eudora 5.1.1 and 5.0-J for Windows, and possibly other versions, allows remote attackers to execute arbitrary code via a multi-part message with a long boundary string.
popauth utility in Qualcomm Qpopper 4.0 and earlier allows local users to overwrite arbitrary files and execute commands as the pop user via a symlink attack on the -trace file option.
Eudora 5.0.2 allows a remote attacker to read arbitrary files via an email with the path of the target file in the "Attachment Converted" MIME header, which sends the file when the email is forwarded to the attacker by the user.
qpopper POP server creates lock files with predictable names, which allows local users to cause a denial of service for other users (lack of mail access) by creating lock files for other mail boxes.