CVE-2026-47180
Published:July 17, 2026
Updated:July 21, 2026
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.
Affected Packages
https://github.com/python-zeroconf/python-zeroconf.git (GITHUB):
Affected version(s) >=0.14 <0.149.5Fix Suggestion:
Update to version 0.149.5zeroconf (PYTHON):
Affected version(s) >=0.14 <0.149.5Fix Suggestion:
Update to version 0.149.5Additional Notes
The description of this vulnerability differs from MITRE.
Related Resources (9)
Do you need more information?
Contact UsCVSS v4
Base Score:
7.1
Attack Vector
ADJACENT
Attack Complexity
LOW
Attack Requirements
NONE
Privileges Required
NONE
User Interaction
NONE
Vulnerable System Confidentiality
NONE
Vulnerable System Integrity
NONE
Vulnerable System Availability
HIGH
Subsequent System Confidentiality
NONE
Subsequent System Integrity
NONE
Subsequent System Availability
NONE
CVSS v3
Base Score:
6.5
Attack Vector
ADJACENT
Attack Complexity
LOW
Privileges Required
NONE
User Interaction
NONE
Scope
UNCHANGED
Confidentiality
NONE
Integrity
NONE
Availability
HIGH
Weakness Type (CWE)
Uncontrolled Recursion
EPSS
Base Score:
0.23