Log in Start free

Vulnerability · Published May 7, 2021 · Assigned by redhat

CVE-2021-3502

Medium 5.5

In plain English

A medium-severity security flaw in avahi. There are no confirmed reports of exploitation so far. The chance it is exploited in the next 30 days is estimated at 0.4% (higher than 31% of all known vulnerabilities). Fixed versions are available - upgrade the affected package.

Severity (CVSS NVD)5.5Medium
Exploit odds (30 days)0.4%top 68.5% of all CVEs
Exploited in the wildNo reportsnot in CISA KEV
Attack toolingNoneno public tooling known

Official description

A flaw was found in avahi 0.8-5. A reachable assertion is present in avahi_s_host_name_resolver_start function allowing a local attacker to crash the avahi service by requesting hostname resolutions through the avahi socket or dbus methods for invalid hostnames. The highest threat from this vulnerability is to the service availability.

Affected packages & fixed versions

EcosystemPackageFixed inAdvisory
AlmaLinux:9avahi0.8-15.el9ALSA-2023:6707
AlmaLinux:9avahi-compat-howl0.8-15.el9ALSA-2023:6707
AlmaLinux:9avahi-compat-howl-devel0.8-15.el9ALSA-2023:6707
AlmaLinux:9avahi-compat-libdns_sd0.8-15.el9ALSA-2023:6707
AlmaLinux:9avahi-compat-libdns_sd-devel0.8-15.el9ALSA-2023:6707
AlmaLinux:9avahi-devel0.8-15.el9ALSA-2023:6707
AlmaLinux:9avahi-glib0.8-15.el9ALSA-2023:6707
AlmaLinux:9avahi-glib-devel0.8-15.el9ALSA-2023:6707
AlmaLinux:9avahi-libs0.8-15.el9ALSA-2023:6707
AlmaLinux:9avahi-tools0.8-15.el9ALSA-2023:6707
Alpine:v3.20avahi0.8-r5ALPINE-CVE-2021-3502
Alpine:v3.21avahi0.8-r5ALPINE-CVE-2021-3502
Alpine:v3.22avahi0.8-r5ALPINE-CVE-2021-3502
Alpine:v3.23avahi0.8-r5ALPINE-CVE-2021-3502
Alpine:v3.24avahi0.8-r5ALPINE-CVE-2021-3502
Debian:12avahi0.8-6DEBIAN-CVE-2021-3502
Debian:13avahi0.8-6DEBIAN-CVE-2021-3502
Debian:14avahi0.8-6DEBIAN-CVE-2021-3502
Ubuntu:22.04:LTSavahi0.8-5ubuntu4UBUNTU-CVE-2021-3502

Affected products (as reported)

VendorProductVersions
n/a avahi 0.8-5

Weakness: CWE-617

References