Xpdf: Untrusted search path

Background

Xpdf is a PDF file viewer that runs under the X Window System.

Description

Erik Wallin reported that Gentoo’s Xpdf attempts to read the “xpdfrc” file from the current working directory if it cannot find a “.xpdfrc” file in the user’s home directory. This is caused by a missing definition of the SYSTEM_XPDFRC macro when compiling a repackaged version of Xpdf.

Impact

A local attacker could entice a user to run “xpdf” from a directory containing a specially crafted “xpdfrc” file, resulting in the execution of arbitrary code when attempting to, e.g., print a file.

Workaround

Do not run Xpdf from untrusted working directories.

Resolution

All Xpdf users should upgrade to the latest version:

 # emerge --sync
 # emerge --ask --oneshot --verbose ">=app-text/xpdf-3.02-r2"