CVE-2021-26720
published 2021-02-17CVE-2021-26720: 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…
PriorityP337high7.8CVSS 3.1
AVLACLPRLUINSUCHIHAH
EPSS
0.40%
31.8th percentile
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.
Affected
15 ranges
| Vendor | Product | Version range | Fixed in |
|---|---|---|---|
| avahi | avahi | <= 0.8-4 | — |
| avahi | avahi | >= 0 < 0.8-4 | 0.8-4 |
| avahi | avahi | >= 0 < 0.8-4 | 0.8-4 |
| avahi | avahi | >= 0 < 0.8-4 | 0.8-4 |
| avahi | avahi | >= 0 < 0.8-4 | 0.8-4 |
| debian | avahi | < avahi 0.8-4 (bookworm) | avahi 0.8-4 (bookworm) |
| debian | debian_linux | — | — |
| debian | debian_linux | — | — |
| msrc | azl3_avahi_0.8-1_on_azure_linux_3.0 | — | — |
| msrc | azl3_avahi_0.8-5_on_azure_linux_3.0 | — | — |
| msrc | azure_linux_3.0_arm | — | — |
| msrc | azure_linux_3.0_x64 | — | — |
| msrc | cbl2_avahi_0.8-1_on_cbl_mariner_2.0 | — | — |
| msrc | cbl_mariner_2.0_arm | — | — |
| msrc | cbl_mariner_2.0_x64 | — | — |
CVSS provenance
nvdv3.17.8HIGHCVSS:3.1/AV:L/AC:L/PR:L/UI:N/S:U/C:H/I:H/A:H
nvdv2.04.6MEDIUMAV:L/AC:L/Au:N/C:P/I:P/A:P
osv7.8HIGH
vendor_debian7.8HIGH
vendor_msrc7.8HIGH
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GHSA
GHSA-jhxr-wvf5-hrp6: avahi-daemon-check-dns
ghsa_unreviewed·2022-05-24
CVE-2021-26720 [HIGH] CWE-59 GHSA-jhxr-wvf5-hrp6: avahi-daemon-check-dns
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.
OSV
CVE-2021-26720: avahi-daemon-check-dns
osv·2021-02-17·CVSS 7.8
CVE-2021-26720 [HIGH] CVE-2021-26720: avahi-daemon-check-dns
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.
Microsoft
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 arbitra
vendor_msrc·2021-02-09·CVSS 7.8
CVE-2021-26720 [HIGH] CWE-59 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 arbitra
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.
FAQ: Is Azure Linux the only Microsoft product that includes this open-source library and is therefore potentially affected by this vulnerability?
One of the main benefits to our customers who choose to use the Azure Linux distro is the commitment to keep it up to date with the most recent and most secure versions of the open source libraries with which the distro is composed. Microsoft is committed to transp
Debian
CVE-2021-26720: avahi - avahi-daemon-check-dns.sh in the Debian avahi package through 0.8-4 is executed ...
vendor_debian·2021·CVSS 7.8
CVE-2021-26720 [HIGH] CVE-2021-26720: avahi - avahi-daemon-check-dns.sh in the Debian avahi package through 0.8-4 is executed ...
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.
Scope: local
bookworm: resolved (fixed in 0.8-4)
bullseye: resolved (fixed in 0.8-4)
forky: resolved (fixed in 0.8-4)
sid: resolved (fixed in 0.8-4)
trixie: resolved (fixed in 0.8-4)
No detection rules found.
No public exploits indexed.
No writeups or analysis indexed.
https://bugs.debian.org/cgi-bin/bugreport.cgi?bug=982796https://bugs.launchpad.net/ubuntu/+source/avahi/+bug/1870824https://bugzilla.suse.com/show_bug.cgi?id=1180827https://lists.debian.org/debian-lts-announce/2022/06/msg00009.htmlhttps://metadata.ftp-master.debian.org/changelogs/main/a/avahi/avahi_0.8-4_changeloghttps://packages.debian.org/bullseye/avahi-daemonhttps://packages.debian.org/buster/avahi-daemonhttps://packages.debian.org/sid/avahi-daemonhttps://security-tracker.debian.org/tracker/CVE-2021-26720https://www.openwall.com/lists/oss-security/2021/02/15/2https://bugs.debian.org/cgi-bin/bugreport.cgi?bug=982796https://bugs.launchpad.net/ubuntu/+source/avahi/+bug/1870824https://bugzilla.suse.com/show_bug.cgi?id=1180827https://lists.debian.org/debian-lts-announce/2022/06/msg00009.htmlhttps://metadata.ftp-master.debian.org/changelogs/main/a/avahi/avahi_0.8-4_changeloghttps://packages.debian.org/bullseye/avahi-daemonhttps://packages.debian.org/buster/avahi-daemonhttps://packages.debian.org/sid/avahi-daemonhttps://security-tracker.debian.org/tracker/CVE-2021-26720https://www.openwall.com/lists/oss-security/2021/02/15/2
2021-02-17
Published