CVE-2026-47180

Zeroconf is a pure Python implementation of multicast DNS service discovery. Prior to 0.149.5, DNSIncoming._decode_labels_at_offset recurses once per DNS-name compression pointer, and a single mDNS packet carrying chained pointers can trigger a RecursionError that escapes DNSIncoming.__init__, causing sustained CPU burn, log flooding, and degraded mDNS-dependent features for unauthenticated hosts on the local link over UDP/5353 (224.0.0.251 / ff02::fb). This issue is fixed in version 0.149.5.

CVSS v3 6.5 MEDIUM

6.5^/10

CVSS v3 : MEDIUM

Vector :

Exploitability : 2.8 / Impact : 3.6

Attack Vector ADJACENT_NETWORK

Attack Complexity LOW

Privileges Required NONE

User Interaction NONE

Confidentiality Impact NONE

Integrity Impact NONE

Availability Impact HIGH

Scope UNCHANGED

References

Link	Resource
https://github.com/python-zeroconf/python-zeroconf/commit/f9e23592137f30fdf7ef710dba065da31c79b1cf	Patch
https://github.com/python-zeroconf/python-zeroconf/pull/1719	Issue Tracking Patch
https://github.com/python-zeroconf/python-zeroconf/releases/tag/0.149.5	Release Notes
https://github.com/python-zeroconf/python-zeroconf/security/advisories/GHSA-9pgc-3ccv-5297	Vendor Advisory Patch

Configurations

Configuration 1 (hide)

cpe:2.3:a:paulsm:zeroconf:*:*:*:*:*:python:*:*

History

No history.

Information

Published : 2026-07-17 19:17

Updated : 2026-08-17 19:48

NVD link : CVE-2026-47180

Mitre link : CVE-2026-47180

CVE.ORG link : CVE-2026-47180

JSON object : View

Products Affected

paulsm

zeroconf

CWE

CWE-674

Uncontrolled Recursion

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