Off-by-one error in the rfc822_output_char function in the RFC822BUFFER routines in the University of Washington (UW) c-client library, as used by the UW IMAP toolkit before imap-2007e and other applications, allows context-dependent attackers to cause a denial of service (crash) via an e-mail message that triggers a buffer overflow.

Multiple stack-based buffer overflows in (1) University of Washington IMAP Toolkit 2002 through 2007c, (2) University of Washington Alpine 2.00 and earlier, and (3) Panda IMAP allow (a) local users to gain privileges by specifying a long folder extension argument on the command line to the tmail or dmail program; and (b) remote attackers to execute arbitrary code by sending e-mail to a destination mailbox name composed of a username and '+' character followed by a long string, processed by the tmail or possibly dmail program.

c-client IMAP Client, as used in imap-2002b and Pine 4.53, allows remote malicious IMAP servers to cause a denial of service (crash) and possibly execute arbitrary code via certain large (1) literal and (2) mailbox size values that cause either integer signedness errors or integer overflow errors.