CVE-2026-47184: Paulsm Zeroconf

Medium severity, CVSS 6.5. EPSS: 0.4% chance of exploitation in the next 30 days.

Zeroconf is a pure Python implementation of multicast DNS service discovery. Prior to 0.149.7, DNSCache._async_add inserted every response record into cache, _expirations, _expire_heap, and service_cache without a cap, allowing unauthenticated hosts on the local link over UDP/5353 (224.0.0.251 / ff02::fb) to multicast valid mDNS responses with unique names and cause memory exhaustion, slower cache lookups, slower async_expire passes, and broken discovery, registration, and ServiceBrowser callbacks. This issue is fixed in version 0.149.7.

Affected products

• Paulsm Zeroconf: before 0.149.7 (fixed in 0.149.7)

Published 2026-07-17. Last modified 2026-08-17.