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Comment Executables are interesting, but what about data? (Score 1) 190

Ok, so this will prevent a modified "acrobat.exe" from running without a prompt. But running a properly-signed "acrobat.exe" to open evil.pdf still pwns the machine. You can also completely pwn a system by interacting with PowerShell. Wanna bet that in a corporate environment (which this is intended to help) powershell.exe will be allowed to run? (and thirdly, this functionality already exists since XP, in the form of "Parental Controls" and/or AppLocker.) --Joe

Comment Re:"could be worse than Heartbleed" (Score 1) 318

Bash is still executed even with the multi-argument call to system.

The file /usr/bin/xzgrep is a shell script (note the #!/usr/bin/bash as the first line of the file). It inherits the CGI environment variables from its parent process, in this case the Perl interpreter. And since some of those CGI environment variables are controlled by the attacker (such as the Referrer: and Cookie: headers) the arbitrary code is executed.

And Bash is even executed when you open(INFILE, "/usr/bin/xzgrep error /var/log/my.log|","r") -- because the thing you're running isn't an ELF executable, it's a #!/usr/bin/bash text file.

Yes, there are other ways to do this (call xz directly without the xzgrep wrapper, use IO::Compress::xz, etc).

Comment Re:"could be worse than Heartbleed" (Score 4, Interesting) 318

Ok, perhaps I undermined the importance, but if you are using 'xzgrep' in cgi context in a serious situation, I would say that is still a mistake. Forking and execing in response to an http request is terrible performance wise before getting to the security dubious of it all.

The dhclient-script stuff is pretty significant and I think I would be in a weak position saying that those have no business execing system commands/scripts. However it does suggest it may be worthwhile to have a helper that is non-root with capabilities to allow it to do key stuff to limit it's ability.

# run under mod_perl
print "Content-Type: text/plain\n\n";
system("/usr/bin/xzgrep error /var/log/my.log");

Can you see how this prefectly secure quick CGI to find errors in your log file would result in a system compromise?

Comment Re:"could be worse than Heartbleed" (Score 5, Insightful) 318

Except for the system "utilities" that are actually bash scripts, such as /usr/bin/xzgrep. These are vulnerable to inheriting malicious environment variables from the parent processes even if the overlying process is not a shell script.

The other reasonable vector is the use of environment variables set by your dhcp client before running /etc/sysconfig/if-up.d/* based on whatever is contained in the first DHCPOFFER packet it receives.

Comment Re:Full Disclosure can be found on oss-security... (Score 1) 399

In addition, ANY CGI that calls out to the system may call something that is actually a bash script even if it doesn't look like one.

For example, xzgrep on my Ubuntu system is a bash script, so this is vulnerable:
print("Content-type: text/plain\n\n");
system("xzgrep info /var/log/mylog.xz");

Comment Tax patents/royalties to fund basic research (Score 4, Interesting) 348

I heard this piece on NPR yesterday, and the thing that kept running through my mind is how the pharmaceutical industry is extorting huge profits based on fundamental research-- with much of that happening under NIH grants. Why not set a tax rate on drug patent royalties and use that to fund the NIH?

You have a multi-billion-dollar-sales patented drug? Chip in 0.5% of the revenue to fund NIH grants. Or make your own equivalent grants to truly independant researchers.

Enter into a licensing deal on a drug patent? Chip in 0.5% of the revenue to fund grants.

Comment Re:The important thing (Score 1) 167

Isolate out the caffiene genes, and start adding it to other plants. There are times I'm eating breakfast, and I'm thinking "Why am I only getting caffiene from the coffee? Buzz up them hashbrowns! Perk up that toast! If we can introduce it into animals, think about caffinated eggs, or butter, or cheese. We can finally jitter up the world.

To heck with that, splice that gene into a retrovirus, and let me caffeinate every cell in my body!

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