CVE-2026-48487

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.

Is your site exposed to CVE-2026-48487?

Run a free security scan — no signup, results in seconds.

EPSS — Exploit Prediction

0.0020

Probability of exploitation

0.10%

Percentile rank

EPSS estimates the probability that this vulnerability will be exploited in the wild within the next 30 days. A higher score means more likely to be exploited.

Weakness Type (CWE)

CWE-130 CWE-130

References

Other References

https://github.com/python-zeroconf/python-zeroconf/commit/544449596e645fcaad3834fa0cb614a54f847a82 https://github.com/python-zeroconf/python-zeroconf/issues/1752 https://github.com/python-zeroconf/python-zeroconf/pull/1756 https://github.com/python-zeroconf/python-zeroconf/releases/tag/0.149.16 https://github.com/python-zeroconf/python-zeroconf/security/advisories/GHSA-qc2x-6f54-m6h9

Frequently Asked Questions

What is CVE-2026-48487? +

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.

How do I check if I'm vulnerable to CVE-2026-48487? +

You can use Secably's free Website Scanner to check your website for known vulnerabilities. For infrastructure scanning, use the Port Scanner to identify exposed services that may be affected. Check the vendor advisories linked above for specific patch and version information.

Related Vulnerabilities

CVE-2026-9054

An attacker sending tcp, il, rudp, rudp, or gre packets with a length less than the header size would trigger …

CVE-2026-54466

websocket-driver is a WebSocket protocol handler with pluggable I/O. Prior to 0.7.5, the frame format in draft versions of the …

CVE-2026-18397

This vulnerability enables unauthenticated remote code execution (RCE) on a victim's machine by exploiting a combination of cryptographic weaknesses and …

CVE-2026-94635

Allocation of resources without limits or throttling, Improper handling of length parameter inconsistency vulnerability in Apache Thrift Lua bindings. This …

CVE-2026-6432

Improper bounds validation in EmberZNet SDK versions 9.0.2 and earlier may result in crashes or dynamic memory leakage.

CVE-2026-77619

Vector is a high-performance observability data pipeline. From 0.15.0 until 0.57.0, the logstash source reads a 32-bit compressed-frame length from …