CVE-2023-38470VulnerabilityPublished 2 Nov 2023Updated 3 Nov 2025

CVE-2023-38470: avahi · Reachable Assertion

Affects avahiSource CVE Database V5

Not known to be exploited · CVSS 6.2 Medium.

Data as of 26 Oct 2026, 07:57 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 24% 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 2026-10-26.

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 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 monitor vendor and distribution security advisories for patches addressing CVE-2023-38470 and apply updates promptly once available. In the interim, restrict local access to systems running Avahi to trusted users only, and implement strict access controls and monitoring to detect unusual process crashes or restarts of the Avahi daemon. Employ host-based intrusion detection systems (HIDS) to alert on assertion failures or abnormal Avahi behavior. Consider disabling Avahi on systems where multicast DNS service discovery is not required to reduce the attack surface. For critical environments, conduct regular audits of local user privileges and network segmentation to limit potential exploitation vectors. Additionally, maintain up-to-date backups and incident response plans to quickly recover from potential denial of service incidents.

Description

A vulnerability was found in Avahi. A reachable assertion exists in the avahi_escape_label() function.

Impact

For European organizations, the primary impact of CVE-2023-38470 is the potential for denial of service affecting network service discovery on local networks. This can disrupt automated device and service detection, impacting operational efficiency in environments relying on Avahi for zero-configuration networking, such as enterprise Linux workstations, servers, and IoT deployments. Critical infrastructure or industrial control systems using Avahi-enabled devices could see interruptions in network communications, leading to operational delays or failures. Although the vulnerability does not compromise data confidentiality or integrity, the loss of availability could affect business continuity, especially in sectors with high reliance on local network services. The requirement for local access limits remote exploitation risk, but insider threats or compromised internal hosts could leverage this flaw to cause service outages. The absence of known exploits reduces immediate risk but does not eliminate the need for vigilance.

References

Community reviews

Loading reviews…

Exploitation evidence

What to do

Description

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

Technical details

References

Community reviews

Related threats