Overly broad permissions can turn one compromised account into a much larger security problem. Learn how to reduce unnecessary access, review privileges, and apply least privilege across modern Linux systems. Review Linux Privileges×
Here's an older article on programming security, but still very useful. Is this something you ever considered to be a concern for your systems in the past? Since we last covered the use of Stack Smashing Protection (SSP) the default compiler for Debian Sid has been upgraded to include it, with no need for custom patching. Read on for a brief demonstration of how it can be used to prevent attacks. . The default C compiler for Sid, which will be used in Etch too, is GCC v4.1. This release contains the SSP patch which previously needed to be applied manually (we demonstrated applying this patch for GCC v3.4 a long time ago). Since the SSP patch is included in the compiler by default it is suddenly a lot easier to start working with it. The link for this article located at Debian Administration is no longer available. . Uncover how Buffer Overflow Guard fortifies security in Ubuntu's GCC v5.0, successfully preventing possible intrusions.. Stack Smashing Protection, Debian Security, GCC v4.1, Security Enhancement. . LinuxSecurity.com Team
Everything has security problems, even Linux. An old and obscure problem with the gcc compiler was recently discovered to have left a security hole in essentially every version of Linux that anyone is likely to be running. Here's what you need to know about fixing it.. The problem itself was discovered by Brad Spengler, the hacker behind the open-source network and server security program, grsecurity. What he found was that in some network code, there was a procedure that included a variable that could be set to NULL (no value at all). Now, this didn't appear to be a problem because the programmer also included a test which would return an error-message if the variable turned out to have a NULL value. So far, so good. Unfortunately, the gcc code optimizer on finding that a variable has been assigned a NULL value removed the test! This left a hole, that didn't exist in the original program. Using this hole, and code provided by Spengler, any cracker with sufficient access to a Linux computer could get into the computer's memory and, from there, get into all kinds of mischief. For more on the down and dirty technical details, turn to Jonathan Corbet's story, "Fun with NULL Pointers." The link for this article located at ComputerWorld is no longer available. . The problem itself was discovered by Brad Spengler, the hacker behind the open-source network and se. everything, security, problems, linux, obscure, problem, compiler. . LinuxSecurity.com Team
On April 4, CERT put out a scary advisory about the GNU Compiler Collection (GCC). This advisory raises some interesting issues on when such advisories are appropriate, what programmers must do to write secure code, and whether compilers should perform optimizations which could open up security holes in poorly-written code. Are you a c programmer? This article shows you how to make your code a little more secure. It's a very an important skill to have so take a look.. . On April 4, CERT put out a scary advisory about the GNU Compiler Collection (GCC). This advisory rai. advisory, april, scary, about, compiler, collection, (gcc). . LinuxSecurity.com Team
Get the latest Linux and open source security news straight to your inbox.