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.
{
"cna_assigner": "GitHub_M",
"cwe_ids": [
"CWE-674"
],
"osv_generated_from": "https://github.com/CVEProject/cvelistV5/tree/main/cves/2026/47xxx/CVE-2026-47180.json"
}{
"cpe": "cpe:2.3:a:paulsm:zeroconf:*:*:*:*:*:python:*:*",
"extracted_events": [
{
"introduced": "0"
},
{
"fixed": "0.149.5"
}
],
"source": [
"CPE_RANGE",
"REFERENCES"
]
}