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

Vulnerability from cvelistv5 – Published: 2026-07-17 18:28 – Updated: 2026-07-17 18:28
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
CWE
  • CWE-130 - Improper Handling of Length Parameter Inconsistency
Assigner
References
Impacted products
Show details on NVD website
To clipboard 

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      "affected": [
        {
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          "vendor": "python-zeroconf",
          "versions": [
            {
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              "version": "\u003c 0.149.16"
            }
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        }
      ],
      "metrics": [
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            "attackRequirements": "NONE",
            "attackVector": "ADJACENT",
            "baseScore": 5.3,
            "baseSeverity": "MEDIUM",
            "privilegesRequired": "NONE",
            "subAvailabilityImpact": "NONE",
            "subConfidentialityImpact": "NONE",
            "subIntegrityImpact": "NONE",
            "userInteraction": "NONE",
            "vectorString": "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",
            "version": "4.0",
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            "vulnConfidentialityImpact": "NONE",
            "vulnIntegrityImpact": "LOW"
          }
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          "descriptions": [
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            }
          ]
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      "providerMetadata": {
        "dateUpdated": "2026-07-17T18:28:21.417Z",
        "orgId": "a0819718-46f1-4df5-94e2-005712e83aaa",
        "shortName": "GitHub_M"
      },
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        {
          "name": "https://github.com/python-zeroconf/python-zeroconf/security/advisories/GHSA-qc2x-6f54-m6h9",
          "tags": [
            "x_refsource_CONFIRM"
          ],
          "url": "https://github.com/python-zeroconf/python-zeroconf/security/advisories/GHSA-qc2x-6f54-m6h9"
        },
        {
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          "tags": [
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          "tags": [
            "x_refsource_MISC"
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          "url": "https://github.com/python-zeroconf/python-zeroconf/pull/1756"
        },
        {
          "name": "https://github.com/python-zeroconf/python-zeroconf/commit/544449596e645fcaad3834fa0cb614a54f847a82",
          "tags": [
            "x_refsource_MISC"
          ],
          "url": "https://github.com/python-zeroconf/python-zeroconf/commit/544449596e645fcaad3834fa0cb614a54f847a82"
        },
        {
          "name": "https://github.com/python-zeroconf/python-zeroconf/releases/tag/0.149.16",
          "tags": [
            "x_refsource_MISC"
          ],
          "url": "https://github.com/python-zeroconf/python-zeroconf/releases/tag/0.149.16"
        }
      ],
      "source": {
        "advisory": "GHSA-qc2x-6f54-m6h9",
        "discovery": "UNKNOWN"
      },
      "title": "Zeroconf: Unvalidated rdlength in record payload readers allows LAN-local cache corruption via crafted mDNS packet"
    }
  },
  "cveMetadata": {
    "assignerOrgId": "a0819718-46f1-4df5-94e2-005712e83aaa",
    "assignerShortName": "GitHub_M",
    "cveId": "CVE-2026-48487",
    "datePublished": "2026-07-17T18:28:21.417Z",
    "dateReserved": "2026-05-21T15:33:08.291Z",
    "dateUpdated": "2026-07-17T18:28:21.417Z",
    "state": "PUBLISHED"
  },
  "dataType": "CVE_RECORD",
  "dataVersion": "5.2",
  "vulnerability-lookup:meta": {
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  }
}



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