Ubuntu Security Notice 1367-3 - USN-1367-1 fixed vulnerabilities in libpng. This provides the corresponding update for Thunderbird. Jueri Aedla discovered that libpng did not properly verify the size used when allocating memory during chunk decompression. If a user or automated system using libpng were tricked into opening a specially crafted image, an attacker could exploit this to cause a denial of service or execute code with the privileges of the user invoking the program. Various other issues were also addressed.
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