Ulf Harnhammar has discovered a remotely exploitable buffer
overflow in Elm e-mail client when parsing the Expires header
of an e-mail message:
The attacker only needs to send the victim an e-mail
message. When the victim with that message in his or her
inbox starts Elm or simply views the inbox in an already
started copy of Elm, the buffer overflow will happen
immediately. The overflow is stack-based, and it gives full
control over EIP, EBP and EBX. It is caused by a bad
sscanf(3) call, using a format string containing "%s"
to copy from a long char array to a shorter array.