Xpdf is an open source viewer for Portable Document Format (PDF) files. GPdf is a Gnome-based PDF viewer that includes some Xpdf code.
iDEFENSE reports that the Decrypt::makeFileKey2 function in Xpdf's Decrypt.cc insufficiently checks boundaries when processing /Encrypt /Length tags in PDF files.
An attacker could entice an user to open a specially-crafted PDF file which would trigger a stack overflow, potentially resulting in execution of arbitrary code with the rights of the user running Xpdf or GPdf.
There is no known workaround at this time.
All Xpdf users should upgrade to the latest version:
# emerge --sync
# emerge --ask --oneshot --verbose ">=app-text/xpdf-3.00-r8"
All GPdf users should also upgrade to the latest version:
# emerge --sync
# emerge --ask --oneshot --verbose ">=app-text/gpdf-2.8.2"