Firefox and Opera users have been warned of a flaw in the way the browsers handle an image file that could allow an attacker to see what websites they've visited.
A malicious bitmap file can be created that pulls other information from the browsers' memory. Some of the information that can be captured is random, but at other times could be valuable, the advisory said.
"The harvested data contains various information including parts of other websites, users' favourites and history and other information," Vexillium.org said.
The flaw could also crash Firefox. The vulnerability affects Firefox 126.96.36.199 and previous versions of that browser as well as the beta version of Opera 9.50.
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