Secunia Security Advisory – Ubuntu has issued an update for libpng. This fixes some vulnerabilities, which can be exploited malicious people to cause a DoS (Denial of Service), disclose potentially sensitive information, or potentially compromise an application using the library.
You can download this advisory from the following link: https://packetstormsecurity.com/files/download/75490/sa34106.txt
Source: https://packetstormsecurity.com/files/75490/Secunia-Security-Advisory-34106.html