Improper Handling of Length Parameter Inconsistency Affecting zeroconf package, versions [,0.149.16)
Threat Intelligence
The probability is the direct output of the EPSS model, and conveys an overall sense of the threat of exploitation in the wild. The percentile measures the EPSS probability relative to all known EPSS scores. Note: This data is updated daily, relying on the latest available EPSS model version. Check out the EPSS documentation for more details.
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Test your applications- Snyk IDSNYK-PYTHON-ZEROCONF-17423205
- published23 Jun 2026
- disclosed22 Jun 2026
- creditUnknown
Introduced: 22 Jun 2026
CVE-2026-48487 (opens in a new tab)How to fix?
Upgrade zeroconf to version 0.149.16 or higher.
Overview
zeroconf is a Pure Python Multicast DNS Service Discovery Library (Bonjour/Avahi compatible)
Affected versions of this package are vulnerable to Improper Handling of Length Parameter Inconsistency via the _read_character_string and _read_string functions. An attacker can inject malicious key/value or address records into the cache by sending a crafted mDNS packet with an over-advertised rdlength field, causing downstream consumers to trust attacker-controlled data.
Note: This can be exploited by any unauthenticated host on the local network segment via multicast mDNS responses.
Workaround
This vulnerability can be mitigated by restricting mDNS (UDP/5353) to trusted Layer-2 segments using AP client isolation, guest-network separation, or host firewall rules.