Link Following Affecting avahi package, versions <0.8-4
Threat Intelligence
Do your applications use this vulnerable package?
In a few clicks we can analyze your entire application and see what components are vulnerable in your application, and suggest you quick fixes.
Test your applications- Snyk ID SNYK-DEBIAN12-AVAHI-1541750
- published 16 Feb 2021
- disclosed 17 Feb 2021
Introduced: 16 Feb 2021
CVE-2021-26720 Open this link in a new tabHow to fix?
Upgrade Debian:12 avahi to version 0.8-4 or higher.
NVD Description
Note: Versions mentioned in the description apply only to the upstream avahi package and not the avahi package as distributed by Debian.
See How to fix? for Debian:12 relevant fixed versions and status.
avahi-daemon-check-dns.sh in the Debian avahi package through 0.8-4 is executed as root via /etc/network/if-up.d/avahi-daemon, and allows a local attacker to cause a denial of service or create arbitrary empty files via a symlink attack on files under /run/avahi-daemon. NOTE: this only affects the packaging for Debian GNU/Linux (used indirectly by SUSE), not the upstream Avahi product.
References
- https://security-tracker.debian.org/tracker/CVE-2021-26720
- https://bugs.debian.org/cgi-bin/bugreport.cgi?bug=982796
- https://bugs.launchpad.net/ubuntu/+source/avahi/+bug/1870824
- https://bugzilla.suse.com/show_bug.cgi?id=1180827
- https://metadata.ftp-master.debian.org/changelogs/main/a/avahi/avahi_0.8-4_changelog
- https://packages.debian.org/bullseye/avahi-daemon
- https://packages.debian.org/buster/avahi-daemon
- https://packages.debian.org/sid/avahi-daemon
- https://www.openwall.com/lists/oss-security/2021/02/15/2
- https://lists.debian.org/debian-lts-announce/2022/06/msg00009.html