Integer overflow in Skype client before 1.4.x.84 on Windows, before 1.3.x.17 on Mac OS, before 1.2.x.18 on Linux, and 1.1.x.6 and earlier allows remote attackers to cause a denial of service (crash) via crafted network data with a large Object Counter value, which leads to a resultant heap-based buffer overflow.

Skype 0.92.0.12 and 1.0.0.1 for Linux, and possibly other versions, creates the /usr/share/skype/lang directory with world-writable permissions, which allows local users to modify language files and possibly conduct social engineering or other attacks.