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.

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.