canvas functions can reveal data from random places in memory – Opera Security Advisories

| December 16, 2008
Severity

Moderately severe

Problem description

There is a flaw in the way that certain canvas functions are handled, that can cause the canvas to be painted with very small amounts of data constructed from random memory. The resulting canvas image can be read and analyzed by JavaScript, so an attacker can get random samples of the user’s memory, which may contain sensitive data.

Opera’s response

Opera Software has released Opera 9.51, where this issue has been fixed.

Credits

Thanks to Philip Taylor for reporting this issue to Opera Software.