At 10:35 1/31/95, Frank Wortner wrote:
>On Monday, 30 Jan 1995, Dr. Frederick B. Cohen wrote:
>> The real problem you will encounter is likely that W3 is not
>> secure. For example, .ps files which alter internal files will pass
>> throuhg the firewall to the W3 browser and cause internal damage.
>The problem you describe isn't limited to W3 browsers. In fact, *any*
>system which allows the blind invocation of programs is vulnerable. One
>could just as well send the PostScript "nastygram" you describe through
>email. An email user agent that "conveniently" started a PostScript
>viewer would basically defer any security policy enforcement to the
>viewer just as effectively as a W3 browser.
But W3 browsers that do this (most of them) are much more common than email
agents that do this (few of them).
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