CVE-2026-48045

Zeroconf is a pure Python implementation of multicast DNS service discovery. Prior to 0.149.12, AsyncListener.handle_query_or_defer retained every truncated TC-bit incoming query, each up to _MAX_MSG_ABSOLUTE = 8966 bytes, in self._deferred[addr] and armed a per-address timer in self._timers[addr] without capping the per-address list or distinct addr keys, allowing unauthenticated hosts on the local link over UDP/5353 (224.0.0.251 / ff02::fb) to spoof sources, grow _deferred and _timers, and cause memory exhaustion and quadratic CPU burn. This issue is fixed in version 0.149.12.

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/b22c8ff19c66c68907d220a4823c0950f4fa93f7	Patch
https://github.com/python-zeroconf/python-zeroconf/pull/1751	Issue Tracking Patch
https://github.com/python-zeroconf/python-zeroconf/releases/tag/0.149.12	Release Notes
https://github.com/python-zeroconf/python-zeroconf/security/advisories/GHSA-9663-mqmp-p9mm	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 20:03

NVD link : CVE-2026-48045

Mitre link : CVE-2026-48045

CVE.ORG link : CVE-2026-48045

JSON object : View

Products Affected

paulsm

zeroconf

CWE

CWE-770

Allocation of Resources Without Limits or Throttling

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