libTIFF: Multiple vulnerabilities

Background

libTIFF provides support for reading and manipulating TIFF images.

Description

Tavis Ormandy of the Google Security Team discovered several heap and stack buffer overflows and other flaws in libTIFF. The affected parts include the TIFFFetchShortPair(), TIFFScanLineSize() and EstimateStripByteCounts() functions, and the PixarLog and NeXT RLE decoders.

Impact

A remote attacker could entice a user to open a specially crafted TIFF file, resulting in the possible execution of arbitrary code.

Workaround

There is no known workaround at this time.

Resolution

All libTIFF users should upgrade to the latest version:

 # emerge --sync
 # emerge --ask --oneshot --verbose ">=media-libs/tiff-3.8.2-r2"