CVE-2026-47184CWE-770denial-of-service

CVE-2026-47184

Medium · published July 17, 2026

CVSS v3.1
6.5
EPSS
0%
Percentile
31.8
In the wild
Unconfirmed
What it is

Zeroconf is a pure Python implementation of multicast DNS service discovery. Prior to 0.149.7, DNSCache._async_add inserted every response record into cache, _expirations, _expire_heap, and service_cache without a cap, allowing unauthenticated hosts on the local link over UDP/5353 (224.0.0.251 / ff02::fb) to multicast valid mDNS responses with unique names and cause memory exhaustion, slower cache lookups, slower async_expire passes, and broken discovery, registration, and ServiceBrowser callbacks. This issue is fixed in version 0.149.7.

The record
Technical detail
CVSS v3.1
6.5 · MEDIUM
Vector
CVSS:3.1/AV:A/AC:L/PR:N/UI:N/S:U/C:N/I:N/A:H
CVSS v4.0
Not supplied
EPSS
0.00389 · 31.8th percentile
Weakness
CWE-770 · Allocation of Resources Without Limits or Throttling
Published
2026-07-17T23:17Z
Affected products (1)
ProductVersionsFixed in
paulsm/zeroconf< 0.149.70.149.7
References (5)
https://github.com/python-zeroconf/python-zeroconf/commit/0ad3f37b5b852b8f614d322283d148efb2cef6e4 · [email protected]https://github.com/python-zeroconf/python-zeroconf/issues/1715 · [email protected]https://github.com/python-zeroconf/python-zeroconf/pull/1718 · [email protected]https://github.com/python-zeroconf/python-zeroconf/releases/tag/0.149.7 · [email protected]https://github.com/python-zeroconf/python-zeroconf/security/advisories/GHSA-rfg2-pjw2-56x2 · [email protected]
EPSS history
Timeline
  • 17 JUL 18:25Z
    Zeroconf: Unbounded DNS record cache allows LAN-local memory exhaustion via multicast flood
    cvelistv5