CVE-2026-47183: 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 0.149.6, DNSIncoming._log_exception_debug and the four QuietLogger exception-dedup methods stored an unbounded _seen_logs dictionary keyed by attacker-influenced IncomingDecodeError messages, retaining sys.exc_info() tracebacks whose frame locals kept raw packet self.data buffers and allowing unauthenticated hosts on the local link over UDP/5353 (224.0.0.251 / ff02::fb) to drive memory growth until mDNS-dependent features degrade or the process is OOM-killed. This issue is fixed in version 0.149.6.

Affected products

• Paulsm Zeroconf: before 0.149.6 (fixed in 0.149.6)

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