CVE-2026-47180: 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 0.149.5, DNSIncoming._decode_labels_at_offset recurses once per DNS-name compression pointer, and a single mDNS packet carrying chained pointers can trigger a RecursionError that escapes DNSIncoming.__init__, causing sustained CPU burn, log flooding, and degraded mDNS-dependent features for unauthenticated hosts on the local link over UDP/5353 (224.0.0.251 / ff02::fb). This issue is fixed in version 0.149.5.

Affected products

• Paulsm Zeroconf: before 0.149.5 (fixed in 0.149.5)

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