XnView is software to view and convert graphics files. XPixMap (XPM) is a simple ascii-based graphics format.
XnView is vulnerable to a stack-based buffer overflow while processing an XPM file with an overly long section string (greater than 1024 bytes).
An attacker could entice a user to view a specially crafted XPM file with XnView that could trigger the vulnerability and possibly execute arbitrary code with the rights of the user running XnView.
There is no known workaround at this time.
No update appears to be forthcoming from the XnView developer and XnView is proprietary, so the XnView package has been masked in Portage. We recommend that users select an alternate graphics viewer and conversion utility, and unmerge XnView:
# emerge --unmerge xnview