CVE-2026-47180 — Zeroconf: Unbounded recursion in DNS compression-pointer decoder allows LAN-local denial of service
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 pointe…
Published: 2026-07-17 · CVSS: 6.5 · CVSS 3.1
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.
Source: CVE Program · Revision 8b16575c39f1e1810c5e863010da073d2d3285e7