Libpng could be made to run programs as your login if it opened a specially crafted file.
Frank Busse discovered that libpng did not properly handle certain malformed PNG images. If a user or automated system were tricked into opening a crafted PNG file, an attacker could cause libpng to crash, resulting in a denial of service. This issue only affected Ubuntu 10.04 LTS, 10.10, and 11.04. (CVE-2011-2501)
26 July 2011
A security issue affects these releases of Ubuntu and its derivatives:
Libpng could be made to run programs as your login if it opened a specially crafted file.
Frank Busse discovered that libpng did not properly handle certain malformed PNG images. If a user or automated system were tricked into opening a crafted PNG file, an attacker could cause libpng to crash, resulting in a denial of service. This issue only affected Ubuntu 10.04 LTS, 10.10, and 11.04. (CVE-2011-2501)
It was discovered that libpng did not properly handle certain malformed PNG images. If a user or automated system were tricked into opening a crafted PNG file, an attacker could cause a denial of service or possibly execute arbitrary code with the privileges of the user invoking the program. (CVE-2011-2690)
Frank Busse discovered that libpng did not properly handle certain PNG images with invalid sCAL chunks. If a user or automated system were tricked into opening a crafted PNG file, an attacker could cause a denial of service or possibly execute arbitrary code with the privileges of the user invoking the program. (CVE-2011-2692)
The problem can be corrected by updating your system to the following package versions:
To update your system, please follow these instructions: https://wiki.ubuntu.com/Security/Upgrades.
After a standard system update you need to reboot your computer to make all the necessary changes.
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