Microsoft Outlook Express 5.5 and 6 allows attackers to cause a denial of service (application crash) via a malformed e-mail header.
https://oval.cisecurity.org/repository/search/definition/oval%3Aorg.mitre.oval%3Adef%3A3376
https://oval.cisecurity.org/repository/search/definition/oval%3Aorg.mitre.oval%3Adef%3A2657
https://oval.cisecurity.org/repository/search/definition/oval%3Aorg.mitre.oval%3Adef%3A2137
https://oval.cisecurity.org/repository/search/definition/oval%3Aorg.mitre.oval%3Adef%3A1950
https://exchange.xforce.ibmcloud.com/vulnerabilities/16585
https://docs.microsoft.com/en-us/security-updates/securitybulletins/2004/ms04-018