CVE-2021-26720

MITRE NVD CVE.ORG Print: PDF PDF

Summary

CVECVE-2021-26720
StatePUBLIC
Assigner[email protected]
Source PriorityCVE Program / NVD first with legacy fallback
Published2021-02-17 22:15:00 UTC
Updated2022-12-06 21:52:00 UTC
Descriptionavahi-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.

Risk And Classification

Problem Types: CWE-59

NVD Known Affected Configurations (CPE 2.3)

TypeVendorProductVersionUpdateEditionLanguage
Application Avahi Avahi All All All All
Operating System Debian Debian Linux 10.0 All All All
Operating System Debian Debian Linux 9.0 All All All
Operating System Debian Debian Linux 10.0 All All All
Operating System Debian Debian Linux 9.0 All All All

References

ReferenceSourceLinkTags
Bug 1180827 – VUL-0: CVE-2021-26720: avahi: outdated and insecure if-up script avahi-daemon-check-dns.sh MISC bugzilla.suse.com Issue Tracking, Third Party Advisory
Bug #1870824 “Errors in script /usr/lib/avahi/avahi-daemon-check...” : Bugs : avahi package : Ubuntu MISC bugs.launchpad.net Issue Tracking, Third Party Advisory
Debian -- Details of package avahi-daemon in sid MISC packages.debian.org Product, Third Party Advisory
404 Not Found MISC metadata.ftp-master.debian.org Broken Link, Third Party Advisory
#982796 - buster-pu: package avahi/0.7-4 - Debian Bug report logs MISC bugs.debian.org Mailing List, Third Party Advisory
[SECURITY] [DLA 3047-1] avahi security update MLIST lists.debian.org
CVE-2021-26720 MISC security-tracker.debian.org Third Party Advisory
Debian -- Details of package avahi-daemon in buster MISC packages.debian.org Product, Third Party Advisory
oss-security - CVE-2021-26720: avahi-daemon: 'avahi' to 'root' user privilege escalation through Debian specific if-up script avahi-daemon-check-dns.sh MISC www.openwall.com Mailing List, Third Party Advisory
Debian -- Details of package avahi-daemon in bullseye MISC packages.debian.org Product, Third Party Advisory
CVE Program record CVE.ORG www.cve.org canonical
NVD vulnerability detail NVD nvd.nist.gov canonical, analysis

Legacy QID Mappings

  • 179359 Debian Security Update for avahi (DLA 3047-1)
  • 179993 Debian Security Update for avahi (CVE-2021-26720)
  • 750101 SUSE Enterprise Linux Security Update for avahi (SUSE-SU-2021:1845-1)
  • 750337 OpenSUSE Security Update for avahi (openSUSE-SU-2021:0370-1)
  • 750789 OpenSUSE Security Update for avahi (openSUSE-SU-2021:1845-1)
  • 901804 Common Base Linux Mariner (CBL-Mariner) Security Update for avahi (6323-1)
  • 906451 Common Base Linux Mariner (CBL-Mariner) Security Update for avahi (6323-2)
© CVE.report 2026 |

Use of this information constitutes acceptance for use in an AS IS condition. There are NO warranties, implied or otherwise, with regard to this information or its use. Any use of this information is at the user's risk. It is the responsibility of user to evaluate the accuracy, completeness or usefulness of any information, opinion, advice or other content. EACH USER WILL BE SOLELY RESPONSIBLE FOR ANY consequences of his or her direct or indirect use of this web site. ALL WARRANTIES OF ANY KIND ARE EXPRESSLY DISCLAIMED. This site will NOT BE LIABLE FOR ANY DIRECT, INDIRECT or any other kind of loss.

CVE, CWE, and OVAL are registred trademarks of The MITRE Corporation and the authoritative source of CVE content is MITRE's CVE web site. This site includes MITRE data granted under the following license.

CVE.report and Source URL Uptime Status status.cve.report