VulnerabilityPublished 2 Nov 2023Updated 3 Nov 2025

CVE-2023-38471: avahi · Reachable Assertion

Affects avahiSource CVE Database V5

Not known to be exploited · CVSS 6.2 Medium.

Data as of 26 Oct 2026, 10:12 UTC

CVSS 3.1 base score

6.2Medium

How severe the flaw is on the 0–10 CVSS scale.

EPSS: 0.3% chance of exploitation in 30 days – higher than 25% of CVEsExploit Prediction Scoring System: the likelihood attackers will use this flaw soon.

CVSS:3.1/AV:L/AC:L/PR:N/UI:N/S:U/C:N/I:N/A:H

Attack Vector: Local
Attack Complexity: Low
Privileges Required: None
User Interaction: None
Scope: Unchanged
Confidentiality: None
Integrity: None
Availability: High

Bold values are the worst case: easiest to exploit or largest impact.

Attack Vector: Local: The vulnerable component is not bound to the network stack and the attacker’s path is via read/write/execute capabilities. Either: the attacker exploits the vulnerability by accessing the target system locally (e.g., keyboard, console), or remotely (e.g., SSH); or the attacker relies on User Interaction by another person to perform actions required to exploit the vulnerability (e.g., tricking a legitimate user into opening a malicious document).
Attack Complexity: Low: Specialized access conditions or extenuating circumstances do not exist. An attacker can expect repeatable success against the vulnerable component.
Privileges Required: None: The attacker is unauthorized prior to attack, and therefore does not require any access to settings or files to carry out an attack.
User Interaction: None: The vulnerable system can be exploited without any interaction from any user.
Scope: Unchanged: An exploited vulnerability can only affect resources managed by the same security authority. In this case, the vulnerable component and the impacted component are either the same, or both are managed by the same security authority.
Confidentiality: None: There is no loss of confidentiality within the impacted component.
Integrity: None: There is no loss of integrity within the impacted component.
Availability: High: There is total loss of availability, resulting in the attacker being able to fully deny access to resources in the impacted component; this loss is either sustained (while the attacker continues to deliver the attack) or persistent (the condition persists even after the attack has completed). Alternatively, the attacker has the ability to deny some availability, but the loss of availability presents a direct, serious consequence to the impacted component (e.g., the attacker cannot disrupt existing connections, but can prevent new connections; the attacker can repeatedly exploit a vulnerability that, in each instance of a successful attack, leaks a only small amount of memory, but after repeated exploitation causes a service to become completely unavailable).

Definitions: FIRST CVSS v3.1 specification.

Exploitation evidence

Disclosed: evidence found.
CVE published 2 Nov 2023
Detectable: no evidence on record.
No public nuclei template indexed
Weaponised: no evidence on record.
No public exploit code indexed in Metasploit or Exploit-DB
Exploited in the wildExploited: no evidence on record.
Not in CISA KEV and no source reports exploitation
Observed by OffSeq MirageSeen by Mirage: no evidence on record.
No attack traffic recorded by OffSeq Mirage sensors

A missing step is not evidence of safety. Sources: cve.org (opens in a new tab), the Metasploit, Exploit-DB and nuclei-templates index as of 26 Oct 2026.

Disclosed: The CVE record is public on cve.org. Its publication is t = 0.
Detectable: A public nuclei template can find exposed instances, for defenders and attackers alike.
Weaponised: Public exploit code exists in Metasploit or Exploit-DB, or CISA SSVC or the CVSS exploit maturity reports a public proof of concept.
Exploited in the wild: CISA KEV lists it, CISA SSVC rates exploitation active, or a source reports attacks.
Observed by OffSeq Mirage: OffSeq Mirage honeypot sensors recorded attack traffic for this CVE, or found exposed hosts without attack traffic.

Moments are spaced evenly, not to scale; a dashed line marks a gap of six months or more. Deltas count from t = 0. Sources that give only a date (CISA KEV, Exploit-DB, or a time of exactly 00:00Z) read “same day” rather than hours. Metasploit modules carry the flaw’s disclosure date, not their release date, and nuclei templates carry no date, so both appear above but not on the timeline.

What to do

AI-suggested

Organizations should implement the following specific mitigations: 1) Restrict local access to systems running Avahi to trusted users only, minimizing the risk of local exploitation. 2) Monitor system logs for Avahi daemon crashes or unusual behavior indicative of assertion failures. 3) Automate service monitoring and restart mechanisms to quickly recover from potential crashes and reduce downtime. 4) Stay informed on vendor advisories and apply patches promptly once available, as no official patches are currently linked. 5) Consider disabling Avahi on systems where service discovery is not required, reducing the attack surface. 6) Employ host-based intrusion detection systems (HIDS) to detect anomalous local activity that could trigger the vulnerability. 7) For critical environments, implement network segmentation to isolate systems running Avahi from untrusted users or networks. These targeted actions go beyond generic advice by focusing on local access control, monitoring, and operational resilience specific to the nature of this vulnerability.

Description

A vulnerability was found in Avahi. A reachable assertion exists in the dbus_set_host_name function.

Impact

For European organizations, the primary impact is a denial of service condition affecting network service discovery capabilities. Avahi is commonly used in Linux environments to enable automatic detection of network services such as printers, file shares, and other devices. Disruption of Avahi can lead to degraded user experience, operational delays, and potential interruptions in service-dependent workflows. Critical infrastructure or enterprise environments relying on Avahi for seamless network operations may experience outages or require manual intervention to restore service. While the vulnerability does not expose sensitive data or allow privilege escalation, the availability impact can indirectly affect business continuity and productivity. Organizations with large Linux deployments, including government agencies, research institutions, and enterprises in sectors like manufacturing and telecommunications, may be more vulnerable. The lack of known exploits reduces immediate risk but does not eliminate the threat, especially from insider threats or targeted attacks. The medium severity suggests a moderate risk level that warrants timely remediation to prevent potential service disruptions.

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Exploitation evidence

What to do

Description

AI analysisMachine-generated, updated 3 Nov 2025, 23:39 UTC

Technical details

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