The from_format function in ssmtp.c in ssmtp 2.61 and 2.62, in certain configurations, uses uninitialized memory for the From: field of an e-mail message, which might allow remote attackers to obtain sensitive information (memory contents) in opportunistic circumstances by reading a message.
Exposure of Sensitive Information to an Unauthorized Actor The product exposes sensitive information to an actor that is not explicitly authorized to have access to that information.