Opera before 11.64 does not properly allocate memory for URL strings, which allows remote attackers to execute arbitrary code or cause a denial of service (memory corruption and application crash) via a crafted string.
The product performs operations on a memory buffer, but it reads from or writes to a memory location outside the buffer's intended boundary. This may result in read or write operations on unexpected memory locations that could be linked to other variables, data structures, or internal program data.