Vulnerability Description
Zeroconf is a pure Python implementation of multicast DNS service discovery. Prior to 0.149.12, AsyncListener.handle_query_or_defer retained every truncated TC-bit incoming query, each up to _MAX_MSG_ABSOLUTE = 8966 bytes, in self._deferred[addr] and armed a per-address timer in self._timers[addr] without capping the per-address list or distinct addr keys, allowing unauthenticated hosts on the local link over UDP/5353 (224.0.0.251 / ff02::fb) to spoof sources, grow _deferred and _timers, and cause memory exhaustion and quadratic CPU burn. This issue is fixed in version 0.149.12.
CVSS Score
MEDIUM
Affected Products
| Vendor | Product | Versions |
|---|---|---|
| Paulsm | Zeroconf | < 0.149.12 |
Related Weaknesses (CWE)
References
- https://github.com/python-zeroconf/python-zeroconf/commit/b22c8ff19c66c68907d220Patch
- https://github.com/python-zeroconf/python-zeroconf/pull/1751Issue TrackingPatch
- https://github.com/python-zeroconf/python-zeroconf/releases/tag/0.149.12Release Notes
- https://github.com/python-zeroconf/python-zeroconf/security/advisories/GHSA-9663Vendor AdvisoryPatch
FAQ
What is CVE-2026-48045?
CVE-2026-48045 is a vulnerability with a CVSS score of 6.5 (MEDIUM). Zeroconf is a pure Python implementation of multicast DNS service discovery. Prior to 0.149.12, AsyncListener.handle_query_or_defer retained every truncated TC-bit incoming query, each up to _MAX_MSG_...
How severe is CVE-2026-48045?
CVE-2026-48045 has been rated MEDIUM with a CVSS base score of 6.5/10. Review the CVSS metrics above for detailed severity breakdown.
Is there a patch for CVE-2026-48045?
Check the references section above for vendor advisories and patch information. Affected products include: Paulsm Zeroconf.