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commands.c in qmail, when running on 64 bit platforms with a large amount of virtual memory, allows remote attackers to cause a denial of service and possibly execute arbitrary code via a long SMTP command without a space character, which causes an array to be referenced with a negative index.
Integer signedness error in the qmailput and substdioput functions in qmail, when running on 64 bit platforms with a large amount of virtual memory, allows remote attackers to cause a denial of service and possibly execute arbitrary code via a large number of SMTP RCPT TO commands.
Integer overflow in the strallocreadyplus function in qmail, when running on 64 bit platforms with a large amount of virtual memory, allows remote attackers to cause a denial of service and possibly execute arbitrary code via a large SMTP request.
Denial of service in Qmail through long SMTP commands.