Medium 6.5Published Jul 17, 2026

CVE-2026-47184Zeroconf: Unbounded DNS record cache allows LAN-local memory exhaustion via multicast flood

Updated under an hour ago (Oct 27, 2026, 6:23 PM ET)

Does this affect you?

It affects python-zeroconf and 1 other product. Add what you run to find out whether that includes you.

No exploitation reported and no EPSS estimate yet.

Do this next

Start free and add your stack

Free account, 1 product

Every CVE for python-zeroconf

Exploited in the last 30 days

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.

CVSS: 6.5 MEDIUM (v3.1, CNA)CVSS:3.1/AV:A/AC:L/PR:N/UI:N/S:U/C:N/I:N/A:H
Weakness (CWE): CWE-770
Known exploited: Not in CISA's KEV catalog
EPSS (exploitation in the next 30 days): Not loaded for this CVE
Assigned by: GitHub_M
NVD analysis: Analyzed
Record last updated: Jul 20, 2026
First seen by InfoSec Signals: Oct 9, 2026

Affected products

Affected products

python-zeroconf python-zeroconf python_zeroconf:python_zeroconf (from the name)	before 0.149.7	CNA record
paulsm zeroconf paulsm:zeroconf	before 0.149.7	NVD

References

References

https://github.com/python-zeroconf/python-zeroconf/security/advisories/GHSA-rfg2-pjw2-56x2	x-refsource-confirm, vendor-advisory, patch
https://github.com/python-zeroconf/python-zeroconf/issues/1715	x-refsource-misc, issue-tracking, patch
https://github.com/python-zeroconf/python-zeroconf/pull/1718	x-refsource-misc, issue-tracking, patch
https://github.com/python-zeroconf/python-zeroconf/commit/0ad3f37b5b852b8f614d322283d148efb2cef6e4	x-refsource-misc, patch
https://github.com/python-zeroconf/python-zeroconf/releases/tag/0.149.7	x-refsource-misc, release-notes

The CVE record on cve.org NVD's entry

The CVE record is authoritative. Products marked “from the name” were identified from the CNA's free-text names, not a CPE, and are matched less certainly. This product uses the NVD API but is not endorsed or certified by the NVD.