CVE-2021-26720

CVSS V2 Medium 4.6 CVSS V3 High 7.8
Description
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.
Overview
  • CVE ID
  • CVE-2021-26720
  • Assigner
  • cve@mitre.org
  • Vulnerability Status
  • Analyzed
  • Published Version
  • 2021-02-17T22:15:12
  • Last Modified Date
  • 2022-12-06T21:52:34
Weakness Enumerations
CWE URL
CWE-59 http://cwe.mitre.org/data/definitions/59.html
CPE Configuration (Product)
CPE Vulnerable Operator Version Start Version End
cpe:2.3:a:avahi:avahi:*:*:*:*:*:*:*:* 1 OR 0.8-4
cpe:2.3:o:debian:debian_linux:9.0:*:*:*:*:*:*:* 1 OR
cpe:2.3:o:debian:debian_linux:10.0:*:*:*:*:*:*:* 1 OR
CVSS Version 2
  • Version
  • 2.0
  • Vector String
  • AV:L/AC:L/Au:N/C:P/I:P/A:P
  • Access Vector
  • LOCAL
  • Access Compatibility
  • LOW
  • Authentication
  • NONE
  • Confidentiality Impact
  • PARTIAL
  • Integrity Impact
  • PARTIAL
  • Availability Impact
  • PARTIAL
  • Base Score
  • 4.6
  • Severity
  • MEDIUM
  • Exploitability Score
  • 3.9
  • Impact Score
  • 6.4
CVSS Version 3
  • Version
  • 3.1
  • Vector String
  • CVSS:3.1/AV:L/AC:L/PR:L/UI:N/S:U/C:H/I:H/A:H
  • Attack Vector
  • LOCAL
  • Attack Compatibility
  • LOW
  • Privileges Required
  • LOW
  • User Interaction
  • NONE
  • Scope
  • UNCHANGED
  • Confidentiality Impact
  • HIGH
  • Availability Impact
  • HIGH
  • Base Score
  • 7.8
  • Base Severity
  • HIGH
  • Exploitability Score
  • 1.8
  • Impact Score
  • 5.9
References
Reference URL Reference Tags
https://bugs.debian.org/cgi-bin/bugreport.cgi?bug=982796 Mailing List Third Party Advisory
https://bugs.launchpad.net/ubuntu/+source/avahi/+bug/1870824 Issue Tracking Third Party Advisory
https://bugzilla.suse.com/show_bug.cgi?id=1180827 Issue Tracking Third Party Advisory
https://lists.debian.org/debian-lts-announce/2022/06/msg00009.html
https://metadata.ftp-master.debian.org/changelogs/main/a/avahi/avahi_0.8-4_changelog Broken Link Third Party Advisory
https://packages.debian.org/bullseye/avahi-daemon Product Third Party Advisory
https://packages.debian.org/buster/avahi-daemon Product Third Party Advisory
https://packages.debian.org/sid/avahi-daemon Product Third Party Advisory
https://security-tracker.debian.org/tracker/CVE-2021-26720 Third Party Advisory
https://www.openwall.com/lists/oss-security/2021/02/15/2 Mailing List Third Party Advisory
Sources
Source Name Source URL
NIST https://nvd.nist.gov/vuln/detail/CVE-2021-26720
MITRE https://cve.mitre.org/cgi-bin/cvename.cgi?name=CVE-2021-26720
History
Created Old Value New Value Data Type Notes
2022-05-10 07:21:39 Added to TrackCVE
2022-12-05 22:20:36 2021-02-17T22:15Z 2021-02-17T22:15:12 CVE Published Date updated
2022-12-05 22:20:36 2022-06-07T21:15:14 CVE Modified Date updated
2022-12-05 22:20:36 Undergoing Analysis Vulnerability Status updated
2022-12-05 22:20:40 References updated
2022-12-06 22:12:27 2022-12-06T21:52:34 CVE Modified Date updated
2022-12-06 22:12:27 Undergoing Analysis Analyzed Vulnerability Status updated