LessTif is a clone of OSF/Motif, which is a standard user interface toolkit available on Unix and Linux.
Multiple vulnerabilities, including buffer overflows, out of bounds memory access and directory traversals, have been discovered in libXpm, which is shipped as a part of the X Window System. LessTif, an application that includes libXpm, suffers from the same issues.
A carefully-crafted XPM file could crash applications making use of the LessTif toolkit, potentially allowing the execution of arbitrary code with the privileges of the user running the application.
There is no known workaround at this time.
All LessTif users should upgrade to the latest version:
# emerge --sync
# emerge --ask --oneshot --verbose ">=x11-libs/lesstif-0.94.0"