SquirrelMail is a standards-based webmail package written in PHP.A server-side code injection flaw was found in the SquirrelMail"map_yp_alias" function. If SquirrelMail was configured to retrieve auser's IMAP server address from a Network Information Service (NIS) servervia the "map_yp_alias" function, an unauthenticated, remote attacker usinga specially-crafted username could use this flaw to execute arbitrary codewith the privileges of the web server. (CVE-2009-1579)Multiple cross-site scripting (XSS) flaws were found in SquirrelMail. Anattacker could construct a carefully crafted URL, which once visited by an unsuspecting user, could cause the user's web browser to execute maliciousscript in the context of the visited SquirrelMail web page. (CVE-2009-1578)It was discovered that SquirrelMail did not properly sanitize CascadingStyle Sheets (CSS) directives used in HTML mail. A remote attacker couldsend a specially-crafted email that could place mail content aboveSquirrelMail's controls, possibly allowing phishing and cross-sitescripting attacks. (CVE-2009-1581)Users of squirrelmail should upgrade to this updated package, whichcontains backported patches to correct these issues.