CVE-2021-3502
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
02 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
03 Exploitation and scoring
- Exploitation
- Not assessed. CISA has not published an exploitation assessment for this record, and it is not in the KEV catalog. That is an absence of assessment, not a finding of no risk.
- SSVC decision
- Not assessed by CISA
- EPSS probability
- 0.37% probability of exploitation activity in the next 30 days.
- EPSS percentile
- Equal to or higher than the score of 31.0% of scored records. A rank, not a probability.
- NVD base score
- 5.5 (CVSS v3.x), scored by the NVD independently of the CNA.
- NVD CVSS vector
- CVSS:3.1/AV:L/AC:L/PR:L/UI:N/S:U/C:N/I:N/A:H
- NVD analysis status
- Modified. NVD last modified this record on 2026-06-17.
- Red Hat severity
- Moderate. Red Hat's rating for its own products, not a CVSS rating.
Exploit-prediction scores from FIRST. Independent scoring and analysis status from the NVD. Vendor severity from Red Hat. Exploitation assessment and catalog membership from CISA.
04 Metadata
- Published
- 2021-05-07 11:46Z5 YR AGO
- Last updated
- 2024-08-03 16:53Z2 YR AGO
- Reserved
- 2021-04-15
- Assigning CNA
- redhat
- Record state
- PUBLISHED
- Severity
- Not rated by the issuing CNA
- CNA CVSS vector
- Not published by the issuing CNA
- Weaknesses
- CWE-617Reachable AssertionBase
- Data version
- 5.1
- Document digest
- 66d2e128aa97d0068be37e9d1a8e019a0de347e2542040ae2c08f2db6bfab77c
05 Affected products
06 References
- bugzilla.redhat.comhttps://bugzilla.redhat.com/show_bug.cgi?id=1946914
- github.comhttps://github.com/lathiat/avahi/issues/338
07 Fixed in
AlmaLinux 9
- avahi Fixed in 0.8-15.el9
- avahi-compat-howl Fixed in 0.8-15.el9
- avahi-compat-howl-devel Fixed in 0.8-15.el9
- avahi-compat-libdns_sd Fixed in 0.8-15.el9
- avahi-compat-libdns_sd-devel Fixed in 0.8-15.el9
- avahi-devel Fixed in 0.8-15.el9
- avahi-glib Fixed in 0.8-15.el9
- avahi-glib-devel Fixed in 0.8-15.el9
- avahi-libs Fixed in 0.8-15.el9
- avahi-tools Fixed in 0.8-15.el9
Source: AlmaLinux, AlmaLinux OS. Copyright (c) 2023 AlmaLinux OS. Licensed under MIT License. Received through OSV.dev. Reformatted by exploit.cc.
Arch Linux
- avahi Fixed in 0.8+22+gfd482a7-1
Source: Arch Linux Security Tracker, the Arch Linux security team. Reformatted by exploit.cc.
CloudLinux 9
- avahi Fixed in 0.8-15.el9
- avahi-compat-howl Fixed in 0.8-15.el9
- avahi-compat-howl-devel Fixed in 0.8-15.el9
- avahi-compat-libdns_sd Fixed in 0.8-15.el9
- avahi-compat-libdns_sd-devel Fixed in 0.8-15.el9
- avahi-devel Fixed in 0.8-15.el9
- avahi-glib Fixed in 0.8-15.el9
- avahi-glib-devel Fixed in 0.8-15.el9
- avahi-libs Fixed in 0.8-15.el9
- avahi-tools Fixed in 0.8-15.el9
Derived from AlmaLinux 9. Partial coverage: only packages taken from AlmaLinux 9 are listed.
Source: CloudLinux errata, CloudLinux Inc. Derived from: AlmaLinux, AlmaLinux OS. Copyright (c) 2023 AlmaLinux OS. Licensed under MIT License. Received through OSV.dev. Reformatted by exploit.cc.
Debian 12
- avahi Fixed in 0.8-6
Source: Debian Security Tracker, the Debian security team. Received through OSV.dev. Reformatted by exploit.cc.
Debian 13
- avahi Fixed in 0.8-6
Source: Debian Security Tracker, the Debian security team. Received through OSV.dev. Reformatted by exploit.cc.
Debian 14
- avahi Fixed in 0.8-6
Source: Debian Security Tracker, the Debian security team. Received through OSV.dev. Reformatted by exploit.cc.
Ubuntu 22.04 LTS
- avahi Fixed in 0.8-5ubuntu4
Source: Ubuntu, Canonical Ltd. Licensed under CC BY-SA 4.0. Received through OSV.dev. Reformatted by exploit.cc.
A release or ecosystem missing from this list has no record here. It may be unaffected or not covered by the source. Source notices and licences.