CVE-2026-47183
MEDIUMZeroconf: Unbounded exception-dedup state retains packet buffers via traceback frame locals, enabling LAN-local memory exhaustion
Title source: cnaDescription
Zeroconf is a pure Python implementation of multicast DNS service discovery. Prior to 0.149.6, DNSIncoming._log_exception_debug and the four QuietLogger exception-dedup methods stored an unbounded _seen_logs dictionary keyed by attacker-influenced IncomingDecodeError messages, retaining sys.exc_info() tracebacks whose frame locals kept raw packet self.data buffers and allowing unauthenticated hosts on the local link over UDP/5353 (224.0.0.251 / ff02::fb) to drive memory growth until mDNS-dependent features degrade or the process is OOM-killed. This issue is fixed in version 0.149.6.
References (5)
Core 5
Core References
X_Refsource_Confirm x_refsource_confirm
https://github.com/python-zeroconf/python-zeroconf/security/advisories/GHSA-phvx-9mgw-67r5
X_Refsource_Misc x_refsource_misc
https://github.com/python-zeroconf/python-zeroconf/issues/1714
X_Refsource_Misc x_refsource_misc
https://github.com/python-zeroconf/python-zeroconf/pull/1717
X_Refsource_Misc x_refsource_misc
https://github.com/python-zeroconf/python-zeroconf/commit/95561e28b24922358f1991e38e3a86d70d72dcec
X_Refsource_Misc x_refsource_misc
https://github.com/python-zeroconf/python-zeroconf/releases/tag/0.149.6
Scores
CVSS v3
6.5
EPSS
0.0024
EPSS Percentile
15.4%
Attack Vector
ADJACENT_NETWORK
CVSS:3.1/AV:A/AC:L/PR:N/UI:N/S:U/C:N/I:N/A:H
CISA SSVC
Vulnrichment
Exploitation
none
Automatable
no
Technical Impact
partial
Details
CWE
CWE-400
Status
published
Products (1)
python-zeroconf/python-zeroconf
< 0.149.6
Published
Jul 17, 2026
Tracked Since
Jul 18, 2026