Medium severity · published May 7, 2021
CVE-2021-3502
A flaw was found in avahi 0.8-5
5.5
CVSS
0.4%
EPSS
No
On KEV
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.
CVSS vector
CVSS:3.1/AV:L/AC:L/PR:L/UI:N/S:U/C:N/I:N/A:H
Attack vector
Local
Complexity
Low
Privileges
Low
User interaction
None
Confidentiality
None
Integrity
None
Availability
High
Scope
Unchanged
Exploitation
Is it being used?
Exploit prediction (EPSS)0.4% · higher than 31% of CVEs
Exploited in the wildNo evidence yet
CISA KEVNot listed
Ransomware campaign useNot known
Affected products
Which versions
AV
Avahi · Avahi
0.8-5 · source: NVD
References
NVD
https://nvd.nist.gov/vuln/detail/CVE-2021-3502
CVE.org
https://www.cve.org/CVERecord?id=CVE-2021-3502
Exploit
https://bugzilla.redhat.com/show_bug.cgi?id=1946914
Exploit
https://github.com/lathiat/avahi/issues/338
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