Zeroconf up to 0.149.15 DNS Service Discovery incoming.py _read_character_string/_read_string RDLENGTH information disclosure

Summaryinfo

A vulnerability, which was classified as problematic, was found in Zeroconf up to 0.149.15. Affected is the function _read_character_string/_read_string of the file src/zeroconf/_protocol/incoming.py of the component DNS Service Discovery. Executing a manipulation of the argument RDLENGTH can lead to information disclosure. This vulnerability is handled as CVE-2026-48487. The attack can be executed remotely. There is not any exploit available.

Detailsinfo

A vulnerability was found in Zeroconf up to 0.149.15. It has been declared as problematic. This vulnerability affects the function _read_character_string/_read_string of the file src/zeroconf/_protocol/incoming.py of the component DNS Service Discovery. The manipulation of the argument RDLENGTH with an unknown input leads to a information disclosure vulnerability. The CWE definition for the vulnerability is CWE-200. The product exposes sensitive information to an actor that is not explicitly authorized to have access to that information. As an impact it is known to affect confidentiality. CVE summarizes:

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.

The advisory is available at github.com. This vulnerability was named CVE-2026-48487 since 05/21/2026. The exploitation appears to be easy. The attack can be initiated remotely. No form of authentication is required for a successful exploitation. Technical details are known, but there is no available exploit. This vulnerability is assigned to T1592 by the MITRE ATT&CK project.

The vulnerability scanner Nessus provides a plugin with the ID 327764 (Linux Distros Unpatched Vulnerability : CVE-2026-48487), which helps to determine the existence of the flaw in a target environment.

Upgrading to version 0.149.16 eliminates this vulnerability.

The vulnerability is also documented in the vulnerability database at Tenable (327764). If you want to get best quality of vulnerability data, you may have to visit VulDB.

Productinfo

Name

• Zeroconf

Version

• 0.149.0
• 0.149.1
• 0.149.2
• 0.149.3
• 0.149.4
• 0.149.5
• 0.149.6
• 0.149.7
• 0.149.8
• 0.149.9
• 0.149.10
• 0.149.11
• 0.149.12
• 0.149.13
• 0.149.14
• 0.149.15

CPE 2.3info

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CPE 2.2info

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If you want to get best quality of vulnerability data, you may have to visit VulDB.

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