Reachable Assertion in Avahi - CVE-2021-3502

Vulnerability identifier: #VU83306

CSH Severity: Low

CVSS v4: 4.8 [CVSS:4.0/AV:L/AC:L/AT:N/PR:L/UI:N/VC:N/VI:N/VA:L/SC:N/SI:N/SA:N]

CVE-ID: CVE-2021-3502

CWE-ID: CWE-617

Exploitation vector: Local access

Exploit availability: No public exploit available

The vulnerability allows a local user to perform a denial of service (DoS) attack.

The vulnerability exists due to a reachable assertion within the avahi_s_host_name_resolver_start function. A local user can pass specially crafted input to the application and perform a denial of service (DoS) attack.

Avahi
Oracle Linux
Red Hat Enterprise Linux for x86_64
Red Hat Enterprise Linux for IBM z Systems
Red Hat Enterprise Linux for Power, little endian
Red Hat Enterprise Linux for ARM 64
Ubuntu
OpenShift Logging
Red Hat Migration Toolkit for Applications
libavahi-core7 (Ubuntu package)
avahi-daemon (Ubuntu package)
avahi (Red Hat package)

Install updates from vendor's website.

OpenShift Logging - update to 5.8.1
libavahi-core7 (Ubuntu package) - addressed in versions 0.7-3.1ubuntu1.3, 0.7-4ubuntu7.1, 0.8-3ubuntu1.1, 0.8-5ubuntu3.1
avahi-daemon (Ubuntu package) - addressed in versions 0.7-3.1ubuntu1.3, 0.7-4ubuntu7.1, 0.8-3ubuntu1.1, 0.8-5ubuntu3.1
avahi (Red Hat package) - update to 0.8-15.el9
Red Hat Migration Toolkit for Applications - update to 6.2

• https://github.com/lathiat/avahi/issues/338
• https://bugzilla.redhat.com/show_bug.cgi?id=1946914

• Local denial of service in Avahi
• Multiple vulnerabilities in Oracle Linux
• Red Hat Enterprise Linux 9 update for avahi
• Multiple vulnerabilities in Logging Subsystem 5.8 for Red Hat OpenShift
• Multiple vulnerabilities in Red Hat Migration Toolkit for Applications
• Ubuntu update for avahi