Top all-time · #6840
xorl %eax, %eax
Personal blog · xorl.wordpress.comsecuritysystems
xorl %eax, %eax is a personal blog at xorl.wordpress.com about security and systems. Since 2009, 12 different Hacker News readers have linked it 13 times. The last post was in 2024, but the archive is still widely read.
Too few sampled comments (6) to say how often HN recommends it.?
Why HN links it
HN readers link this blog's low-level technical posts on topics such as Linux kernel exploits, anti-debugging tricks, linker internals, and ASLR. Commenters cite them as examples or sources.
Summarised by Claude from a sample of 6 HN comments that link here. Each comment is marked recommending, critical or neutral (citing without judging); how this works.
What Hacker News says?
> Well, Chelsea Manning was the actual whistleblower in this situation Granted, Manning was the one who provided Wikileaks the files. But, lets not omit that Sara Harrison and Julian were critical in getting Edward out of Hong Kong and his gravitas made the Bitcoin community to go against Satoshi and donated to keep Wikileaks alive and made all of this possible. Cypherpunks are not going to live up to people's ideal…
Comment linking /2017/11/21/opsec-fail-reality-winner-the-intercept/
on “Julian Assange extradition to US blocked by UK court”Submitted CVE-2009-3379: Mozilla Firefox Multiple Vulnerabilities as a story · 14 points
HN discussion"So, again, the exploit was that a telnet session was exporting environment variables." No, this was a feature. It had been safe in the days of static libraries, it became a problem when the LD_something family of variables was introduced. Besides, the telnet was just a single vector of introducing the LD_. Other examples concern local privilege escalation by calling suid apps: http://xorl.wordpress.com/2009/12/01/f…
Comment linking /2009/12/01/freebsd-ld_preload-security-bypass/
on “Opening *.txt file is dangerous on Windows”Submitted Introduction to Linux Security Modules (LSM) as a story · 11 points
HN discussionReminds me tricks people used to crash debuggers. E.g. https://reverse.put.as/2012/01/31/anti-debug-trick-1-abusing... , http://blog.ioactive.com/2012/12/striking-back-gdb-and-ida-d... and https://xorl.wordpress.com/2009/01/05/more-gdb-anti-debuggin...
Comment linking /2009/01/05/more-gdb-anti-debugging/
on “A Sampling of Anti-Decompilation Techniques”Submitted OpenSSH ‘sftp-server’ Remote Security Vulnerability as a story · 5 points
HN discussion> Wow, really? So you can't make system calls from assembly language on Windows? Of course you can. Just go through the system DLL like any other program. > What kind of thunks and security vulnerabilities are you talking about though? Something like http://xorl.wordpress.com/2009/08/07/cve-2007-4573-linux-ker... , though that's not the only one.
Comment linking /2009/08/07/cve-2007-4573-linux-kernel-ia32-system-call-emulation-vulnerability/
on “A ToC of the 20-part linker essay (2008)”Submitted Linux Kernel ASLR Implementation as a story · 3 points
HN discussionAh, (for anyone caring enough to read this discussion) apparently the actual code in the patch (which was more complex than listed here [1]) doesn't just ban processes (as with control of the parent we really do have the ability to bypass the process check, as again: we can just keep making replacement exploit containers), but also bans entire user accounts that are causing suspicious memory accesses. [1] http://xor…
Comment linking /2010/11/09/grkernsec_brute-exploit-bruteforcing-protection/
on “Big problems with ASLR in Ice Cream Sandwich”Submitted FreeBSD Red Zone – Kernel Buffer Corruption Detector as a story · 3 points
HN discussionI seem to recall seeing that as well, and I certainly don't have access to non-public data, but I can't find an example. Of course, there is http://xorl.wordpress.com/2009/07/17/linux-kernel-devnettun-... (discussion at http://lwn.net/Articles/341773/ ), but while that is also an instance of gcc doing non-obvious but correct things, it's not the same problem.
Comment linking /2009/07/17/linux-kernel-devnettun-null-pointer-dereference/
on “C Is Not Assembly”Submitted Offensive Security Private Companies Inventory as a story · 1 points
HN discussionSubmitted US Government Cyber Operations Hacking Groups Poster as a story · 1 points
HN discussion
