GLSA-200408-19 : courier-imap: Remote Format String Vulnerability
High Nessus Plugin ID 14575
SynopsisThe remote Gentoo host is missing one or more security-related patches.
DescriptionThe remote host is affected by the vulnerability described in GLSA-200408-19 (courier-imap: Remote Format String Vulnerability)
There is a format string vulnerability in the auth_debug() function which can be exploited remotely, potentially leading to arbitrary code execution as the user running the IMAP daemon (oftentimes root). A remote attacker may send username or password information containing printf() format tokens (such as '%s'), which will crash the server or cause it to execute arbitrary code.
This vulnerability can only be exploited if DEBUG_LOGIN is set to something other than 0 in the imapd config file.
If DEBUG_LOGIN is enabled in the imapd configuration, a remote attacker may execute arbitrary code as the root user.
Set the DEBUG_LOGIN option in /etc/courier-imap/imapd to 0. (This is the default value.)
SolutionAll courier-imap users should upgrade to the latest version:
# emerge sync # emerge -pv '>=net-mail/courier-imap-3.0.5' # emerge '>=net-mail/courier-imap-3.0.5'