CVE-2025-59529

Published: Dic 18, 2025 Last Modified: Gen 16, 2026
ExploitDB:
Other exploit source:
Google Dorks:
MEDIUM 5,5
Source: [email protected]
Attack Vector: local
Attack Complexity: low
Privileges Required: low
User Interaction: none
Scope: unchanged
Confidentiality: none
Integrity: none
Availability: high

Description

AI Translation Available

Avahi is a system which facilitates service discovery on a local network via the mDNS/DNS-SD protocol suite. In versions up to and including 0.9-rc2, the simple protocol server ignores the documented client limit and accepts unlimited connections, allowing for easy local DoS. Although `CLIENTS_MAX` is defined, `server_work()` unconditionally `accept()`s and `client_new()` always appends the new client and increments `n_clients`. There is no check against the limit. When client cannot be accepted as a result of maximal socket number of avahi-daemon, it logs unconditionally error per each connection. Unprivileged local users can exhaust daemon memory and file descriptors, causing a denial of service system-wide for mDNS/DNS-SD. Exhausting local file descriptors causes increased system load caused by logging errors of each of request. Overloading prevents glibc calls using nss-mdns plugins to resolve `*.local.` names and link-local addresses. As of time of publication, no known patched versions are available, but a candidate fix is available in pull request 808, and some workarounds are available. Simple clients are offered for nss-mdns package functionality. It is not possible to disable the unix socket `/run/avahi-daemon/socket`, but resolution requests received via DBus are not affected directly. Tools avahi-resolve, avahi-resolve-address and avahi-resolve-host-name are not affected, they use DBus interface. It is possible to change permissions of unix socket after avahi-daemon is started. But avahi-daemon does not provide any configuration for it. Additional access restrictions like SELinux can also prevent unwanted tools to access the socket and keep resolution working for trusted users.

EPSS (Exploit Prediction Scoring System)

Trend Analysis

EPSS (Exploit Prediction Scoring System)

Prevede la probabilità di sfruttamento basata su intelligence sulle minacce e sulle caratteristiche della vulnerabilità.

EPSS Score
0,0001
Percentile
0,0th
Updated

EPSS Score Trend (Last 88 Days)

400

Uncontrolled Resource Consumption

Draft
Abstraction: Class Structure: Simple
Common Consequences
Security Scopes Affected:
Availability Access Control Other
Potential Impacts:
Dos: Crash, Exit, Or Restart Dos: Resource Consumption (Cpu) Dos: Resource Consumption (Memory) Dos: Resource Consumption (Other) Bypass Protection Mechanism Other
Applicable Platforms
All platforms may be affected
Likelihood of Exploit: High
View CWE Details
Application

Avahi by Avahi

Product Information
Vendor Avahi
Product Avahi
Version Range Affected
To 0.9 (exclusive)
cpe:2.3:a:avahi:avahi:*:*:*:*:*:*:*:*
Common Platform Enumeration - Standardized vulnerability identification
Application

Avahi by Avahi

Product Information
Vendor Avahi
Product Avahi
Version 0.9
cpe:2.3:a:avahi:avahi:0.9:rc1:*:*:*:*:*:*
Common Platform Enumeration - Standardized vulnerability identification
http://www.openwall.com/lists/oss-security/2025/12/19/1
http://www.openwall.com/lists/oss-security/2025/12/19/1
https://github.com/avahi/avahi/pull/808
https://github.com/avahi/avahi/pull/808
https://github.com/avahi/avahi/security/advisories/GHSA-73w…
https://github.com/avahi/avahi/security/advisories/GHSA-73wf-3xmj-x82q
https://zeropath.com/blog/avahi-simple-protocol-server-dos-…
https://zeropath.com/blog/avahi-simple-protocol-server-dos-cve-2025-59529