Vulnerability Description
Zeroconf is a pure Python implementation of multicast DNS service discovery. Prior to 0.149.16, _read_character_string and _read_string in src/zeroconf/_protocol/incoming.py advanced self.offset by attacker-declared RDLENGTH without checking it against self._data_len, allowing unauthenticated hosts on the local link over UDP/5353 (224.0.0.251 / ff02::fb) to send a TXT, HINFO, or A/AAAA record with rdlength=65535 and seed DNSCache and ServiceInfo.properties with truncated, attacker-shaped key/value or address records. This issue is fixed in version 0.149.16.
CVSS Score
MEDIUM
Affected Products
| Vendor | Product | Versions |
|---|---|---|
| Paulsm | Zeroconf | < 0.149.16 |
Related Weaknesses (CWE)
References
- https://github.com/python-zeroconf/python-zeroconf/commit/544449596e645fcaad3834Patch
- https://github.com/python-zeroconf/python-zeroconf/issues/1752Issue TrackingPatch
- https://github.com/python-zeroconf/python-zeroconf/pull/1756Issue TrackingPatch
- https://github.com/python-zeroconf/python-zeroconf/releases/tag/0.149.16Release Notes
- https://github.com/python-zeroconf/python-zeroconf/security/advisories/GHSA-qc2xVendor Advisory
FAQ
What is CVE-2026-48487?
CVE-2026-48487 is a vulnerability with a CVSS score of 5.3 (MEDIUM). Zeroconf is a pure Python implementation of multicast DNS service discovery. Prior to 0.149.16, _read_character_string and _read_string in src/zeroconf/_protocol/incoming.py advanced self.offset by at...
How severe is CVE-2026-48487?
CVE-2026-48487 has been rated MEDIUM with a CVSS base score of 5.3/10. Review the CVSS metrics above for detailed severity breakdown.
Is there a patch for CVE-2026-48487?
Check the references section above for vendor advisories and patch information. Affected products include: Paulsm Zeroconf.