CVE-2004-1558: Multiple stack-based buffer overflows in YPOPs!

Security readout for executives and security teams

CVE-2004-1558 affects legacy YPOPs!/YahooPOPS 0.4 through 0.6. A remote party can crash the service, and the CVE says code execution may be possible, by sending overly long POP3 USER or SMTP input. Business risk is mainly legacy exposure on systems still running this mail proxy. Exposure is likely limited to legacy hosts still running YPOPs!/YahooPOPS 0.4 through 0.6 and accepting POP3 or SMTP connections from untrusted networks. Modern environments are unlikely to be affected unless old mail proxy software remains installed. Treat as high priority only if legacy YPOPs! is present. The product age lowers likely exposure, but remote memory corruption on an exposed mail service can create outage and potential compromise risk. Mitigation focus: Identify and retire any YPOPs!/YahooPOPS 0.4 through 0.6 installations.; Check vendor or archival project guidance for fixed versions or replacement recommendations.; Restrict POP3 and SMTP exposure to trusted networks only where temporary operation is unavoidable..

Prepared

Jun 30, 2026, 00:25 UTC (UTC+00:00)

Generated from the cited source records. This long-tail analysis has not been individually reviewed by a named human.