CVE-2026-47180 (GCVE-0-2026-47180)

Vulnerability from cvelistv5 – Published: 2026-07-17 18:21 – Updated: 2026-07-17 19:21
VLAI
Title
Zeroconf: Unbounded recursion in DNS compression-pointer decoder allows LAN-local denial of service
Summary
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.
Severity
6.5 (Medium)
CVSS:3.1/AV:A/AC:L/PR:N/UI:N/S:U/C:N/I:N/A:H
SSVC
Exploitation: none Automatable: no Technical Impact: partial
CISA Coordinator · CISA-ADP (v2.0.3)
Decision recorded 2026-07-17 19:21 UTC
CWE
Assigner
References
Impacted products
Vendor Product Version CPE status
python-zeroconf python-zeroconf Affected: < 0.149.5
guessed Create a notification for this product.
Show details on NVD website
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