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

No CVSS.

References

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

Configurations

No configuration.

History

17 Jul 2026, 19:17

Type	Values Removed	Values Added
New CVE

Information

Published : 2026-07-17 19:17

Updated : 2026-07-20 20:16

NVD link : CVE-2026-48487

Mitre link : CVE-2026-48487

CVE.ORG link : CVE-2026-48487

JSON object : View

Products Affected

No product.

CWE

CWE-130

Improper Handling of Length Parameter Inconsistency

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