Ask Klaus
DNS Security Bug
What's the easiest way to get rid of the dangerous "DNS resolver" security bug that was recently detected (CVE-2015-7547)? Security lists tell me that all programs that resolve Internet names to IP addresses are affected, such as Firefox, LibreOffice, and various KDE and Gnome programs. Do I have to upgrade all of them?
It is the GLIBC implementation of the C libraries getaddrinfo() function that causes a stack overflow in case of specially crafted answers from a direct name server query. Programs can crash or execute arbitrary code due to this bug, but in order to exploit it, the attacker must first manipulate a DNS server that's queried by your client system. If your Linux system is behind an access point or router that acts as a DNS proxy, chances are that you are safe, because the DNS proxy may already replace bad replies by an "address not available" response. However, you should upgrade as soon as possible anyway – not the entire system, but definitely the glibc libraries that contain the vulnerability.
For Debian-based systems, updating the libc6 package is sufficient to fix all programs dynamically linked with libc6; these are the commands for Knoppix/Debian:
[...]
Buy this article as PDF
(incl. VAT)
Buy Linux Magazine
US / Canada
UK / Australia
Subscribe to our Linux Newsletters
Find Linux and Open Source Jobs
Subscribe to our ADMIN Newsletters
Support Our Work
Linux Magazine content is made possible with support from readers like you. Please consider contributing when you’ve found an article to be beneficial.
News
-
Linux Kernel 6.17 Drops bcachefs
After a clash over some late fixes and disagreements between bcachefs's lead developer and Linus Torvalds, bachefs is out.
-
ONLYOFFICE v9 Embraces AI
Like nearly all office suites on the market (except LibreOffice), ONLYOFFICE has decided to go the AI route.
-
Two Local Privilege Escalation Flaws Discovered in Linux
Qualys researchers have discovered two local privilege escalation vulnerabilities that allow hackers to gain root privileges on major Linux distributions.
-
New TUXEDO InfinityBook Pro Powered by AMD Ryzen AI 300
The TUXEDO InfinityBook Pro 14 Gen10 offers serious power that is ready for your business, development, or entertainment needs.
-
Danish Ministry of Digital Affairs Transitions to Linux
Another major organization has decided to kick Microsoft Windows and Office to the curb in favor of Linux.
-
Linux Mint 20 Reaches EOL
With Linux Mint 20 at its end of life, the time has arrived to upgrade to Linux Mint 22.
-
TuxCare Announces Support for AlmaLinux 9.2
Thanks to TuxCare, AlmaLinux 9.2 (and soon version 9.6) now enjoys years of ongoing patching and compliance.
-
Go-Based Botnet Attacking IoT Devices
Using an SSH credential brute-force attack, the Go-based PumaBot is exploiting IoT devices everywhere.
-
Plasma 6.5 Promises Better Memory Optimization
With the stable Plasma 6.4 on the horizon, KDE has a few new tricks up its sleeve for Plasma 6.5.
-
KaOS 2025.05 Officially Qt5 Free
If you're a fan of independent Linux distributions, the team behind KaOS is proud to announce the latest iteration that includes kernel 6.14 and KDE's Plasma 6.3.5.