ArchLinux: 201504-26: powerdns: denial of service
Summary
A bug was discovered in our label decompression code, making it possible for names to refer to themselves, thus causing a loop during decompression. This loop is capped at a 1000 iterations by a failsafe, making the issue harmless on most platforms. However, on specific platforms, the recursion involved in these 1000 steps causes memory corruption leading to a quick crash, presumably because the default stack is too small.
Resolution
Upgrade to 3.4.4-1.
# pacman -Syu "powerdns>=3.4.4-1"
The problem has been fixed upstream in version 3.4.4.
References
https://doc.powerdns.com/md/security/powerdns-advisory-2015-01/ https://access.redhat.com/security/cve/CVE-2015-1868 https://bugs.archlinux.org/task/44708
![Dist Arch](/images/distros/dist-arch.png)
Workaround
Exposure can be limited by configuring the allow-from setting so only trusted users can query your nameserver.