KOffice is an integrated office suite for KDE. koffice-libs is a package containing shared librares used by KOffice programs.
Kees Cook of Ubuntu discovered that 'KLaola::readBigBlockDepot()' in klaola.cc fills 'num_of_bbd_blocks' while reading a .ppt (PowerPoint) file without proper sanitizing, resulting in an integer overflow subsequently overwriting the heap with parts of the file being read.
By enticing a user to open a specially crafted PowerPoint file, an attacker could crash the application and possibly execute arbitrary code with the rights of the user running KOffice.
There is no known workaround at this time.
All koffice-libs users should upgrade to the latest version:
# emerge --sync
# emerge --ask --oneshot --verbose ">=app-office/koffice-libs-1.5.0"