Full Disclosure mailing list archives
Re: Firefox 2.0.0.7 has a very serious calculation bug [FIB FOUND/CONFIRMED]
From: "Susam Pal" <susam.pal () gmail com>
Date: Fri, 28 Sep 2007 23:28:32 +0530
Compile and run this. #include <stdio.h> int main(int argc, char **argv) { float a = 0.7; if(a == 0.7) { printf("%f is equal to %f\n", a, 0.7); } else { printf("%f is not equal to %f\n", a, 0.7); } } On many implementations (not necessarily all implementations) you will get the output as:- 0.700000 is not equal to 0.700000 For example, on my Debian Etch with gcc 4.1.2, the output is as shown above. This doesn't mean it is a bug in 'gcc'. It's just a limitation of floating point math. If someone doesn't take care of the floating point behavior while writing code in JavaScript, it is a bug in the JavaScript code and not a bug in Firefox. Regards, Susam Pal http://susam.in/ On 9/28/07, blah <blah () blakogre com> wrote:
IE7 was fine for me, showed up in FF 2.0.0.7 However, I think it's much wider-spread than initially thought. I found the same most unsettling results using: javascript:4.2-0.1 javascript:3.2-0.1 javascript:2.2-0.1 I did not have time to try more, but obviously all of you can see the possibilities. Because it appears this works with any number, I've dubbed it the FIB, (Firefox Infinite Bug). I think this should get its own exploit category, too, since assuredly, perhaps one day, this will be exploitable. On 9/28/07, Steven Adair <steven () securityzone org> wrote:So are we dealing with an RDCB (Recently Disclosed Calculation Bug) or was this just a mistake? StevenActually, I see 5.1000000000000005 in both browsers. Larry Seltzer eWEEK.com Security Center Editor_______________________________________________ Full-Disclosure - We believe in it. Charter: http://lists.grok.org.uk/full-disclosure-charter.html Hosted and sponsored by Secunia - http://secunia.com/
_______________________________________________ Full-Disclosure - We believe in it. Charter: http://lists.grok.org.uk/full-disclosure-charter.html Hosted and sponsored by Secunia - http://secunia.com/
Current thread:
- Re: Firefox 2.0.0.7 has a very serious calculation bug [FIB FOUND/CONFIRMED] blah (Sep 28)
- Re: Firefox 2.0.0.7 has a very serious calculation bug [FIB FOUND/CONFIRMED] Larry Seltzer (Sep 28)
- Re: Firefox 2.0.0.7 has a very serious calculation bug [FIB FOUND/CONFIRMED] Susam Pal (Sep 29)