It was reported [1] that when KDE encounters an "internal server error" and also prints out the URL that caused the error that it would include the username and password (if supplied) to the resource that caused the error. For instance, it would show "https://user:password@remotehost.com" or similar. This is due to kioslave/http/http.cpp using mrequest.url.url() rather than the sanitized mrequest.url.prettyUrl(). This issue is fixed in git [2].

Note that this information is printed out to the local user actively using the computer.

[1] https://bugs.kde.org/showbug.cgi?id=319428 [2] https://projects.kde.org/projects/kde/kdelibs/repository/revisions/65d736dab592bced4410ccfa4699de89f78c96ca/diff/kioslave/http/http.cpp

KDE kdelibs before 4.14 and kauth before 5.1 does not properly use D-Bus for communication with a polkit authority, which allows local users to bypass intended access restrictions by leveraging a PolkitUnixProcess PolkitSubject race condition via a (1) setuid process or (2) pkexec process, related to CVE-2013-4288 and "PID reuse race conditions."