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CVE-2026-48487 (GCVE-0-2026-48487)

Vulnerability from cvelistv5 – Published: 2026-07-17 18:28 – Updated: 2026-07-20 19:26
VLAI
Title
Zeroconf: Unvalidated rdlength in record payload readers allows LAN-local cache corruption via crafted mDNS packet
Summary
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.
Severity
5.3 (Medium)
CVSS:4.0/AV:A/AC:L/AT:N/PR:N/UI:N/VC:N/VI:L/VA:N/SC:N/SI:N/SA:N
SSVC
Exploitation: none Automatable: no Technical Impact: partial
CISA Coordinator · CISA-ADP (v2.0.3)
Decision recorded 2026-07-20 19:25 UTC
CWE
  • CWE-130 - Improper Handling of Length Parameter Inconsistency
Assigner
References
Impacted products
Vendor Product Version CPE status
python-zeroconf python-zeroconf Affected: < 0.149.16
guessed Create a notification for this product.
Show details on NVD website
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