Opera before 12.12 does not properly allocate memory for GIF images, which allows remote attackers to execute arbitrary code or cause a denial of service (memory overwrite) via a malformed image.
http://www.opera.com/support/kb/view/1038/
http://www.opera.com/docs/changelogs/unified/1212/
Source: Mitre, NVD
Published: 2013-01-02
Updated: 2013-01-02
Base Score: 9.3
Vector: CVSS2#AV:N/AC:M/Au:N/C:C/I:C/A:C
Severity: High
Base Score: 9.8
Vector: CVSS:3.0/AV:N/AC:L/PR:N/UI:N/S:U/C:H/I:H/A:H
Severity: Critical