Users of Netscape 7.2 and 6.2.3 have been advised to abandon the software owing to a flaw in the way the browser handles images.
A new critical advisory from Danish security watchdog Secunia warns that a buffer overflow vulnerability in the way the browser handles GIF images could cause systems to crash or allow malicious code onto a machine without the user's knowledge.
The only advice the firm offers to deal with the problem is to "use another product".
The flaw is similar to one that plagued the Mozilla browser, for which a patch was released last month.
Netscape was informed of the flaw by an outside security expert. A patch has not yet been released. The company was unavailable for comment at time of going to press.
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