CVE-2026-48487

Zeroconf is a pure Python implementation of multicast DNS service discovery. Prior to 0.149.16, _read_character_string and _read_string in src/zeroconf/_protocol/incoming.py advanced self.offset by attacker-declared RDLENGTH without checking it against self._data_len, allowing unauthenticated hosts on the local link over UDP/5353 (224.0.0.251 / ff02::fb) to send a TXT, HINFO, or A/AAAA record with rdlength=65535 and seed DNSCache and ServiceInfo.properties with truncated, attacker-shaped key/value or address records. This issue is fixed in version 0.149.16.

CVSS v3 5.3 MEDIUM

5.3^/10

CVSS v3 : MEDIUM

Vector :

Exploitability : 3.9 / Impact : 1.4

Attack Vector NETWORK

Attack Complexity LOW

Privileges Required NONE

User Interaction NONE

Confidentiality Impact NONE

Integrity Impact LOW

Availability Impact NONE

Scope UNCHANGED

References

Link	Resource
https://github.com/python-zeroconf/python-zeroconf/commit/544449596e645fcaad3834fa0cb614a54f847a82	Patch
https://github.com/python-zeroconf/python-zeroconf/issues/1752	Issue Tracking Patch
https://github.com/python-zeroconf/python-zeroconf/pull/1756	Issue Tracking Patch
https://github.com/python-zeroconf/python-zeroconf/releases/tag/0.149.16	Release Notes
https://github.com/python-zeroconf/python-zeroconf/security/advisories/GHSA-qc2x-6f54-m6h9	Vendor Advisory

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 20:06

NVD link : CVE-2026-48487

Mitre link : CVE-2026-48487

CVE.ORG link : CVE-2026-48487

JSON object : View

Products Affected

paulsm

zeroconf

CWE

CWE-130

Improper Handling of Length Parameter Inconsistency

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