FastNetMon Community Edition through 1.2.9 contains an out-of-bounds read vulnerability in the NetFlow v9 data flowset processor. In src/netflow_plugin/netflow_v9_collector.cpp, the Data template branch (lines 1695-1702) iterates over flow records without performing a per-iteration bounds check against the packet end pointer. In contrast, the Options template branch (lines 1709-1719) correctly checks 'if (pkt + offset + field_template->total_length > packet_end)' before each iteration. The Data branch omits this check entirely. Since template definitions are sent by the network peer (and are unauthenticated UDP), an attacker can craft templates that cause the parser to read arbitrary memory past the packet buffer. This can leak sensitive memory contents or cause a crash.
History

Wed, 27 May 2026 01:15:00 +0000

Type Values Removed Values Added
Title Out-of-Bounds Read in FastNetMon NetFlow v9 Collector

Tue, 26 May 2026 23:30:00 +0000

Type Values Removed Values Added
Title Unhandled Bounds Check in FastNetMon NetFlow v9 Parser Allows Memory Leak or Crash
Weaknesses CWE-200
CWE-787

Tue, 26 May 2026 21:30:00 +0000

Type Values Removed Values Added
Weaknesses CWE-125
Metrics cvssV3_1

{'score': 6.5, 'vector': 'CVSS:3.1/AV:N/AC:L/PR:L/UI:N/S:U/C:H/I:N/A:N'}

ssvc

{'options': {'Automatable': 'no', 'Exploitation': 'none', 'Technical Impact': 'partial'}, 'version': '2.0.3'}


Tue, 26 May 2026 16:45:00 +0000

Type Values Removed Values Added
Title Unhandled Bounds Check in FastNetMon NetFlow v9 Parser Allows Memory Leak or Crash
Weaknesses CWE-200
CWE-787

Tue, 26 May 2026 15:45:00 +0000

Type Values Removed Values Added
Description FastNetMon Community Edition through 1.2.9 contains an out-of-bounds read vulnerability in the NetFlow v9 data flowset processor. In src/netflow_plugin/netflow_v9_collector.cpp, the Data template branch (lines 1695-1702) iterates over flow records without performing a per-iteration bounds check against the packet end pointer. In contrast, the Options template branch (lines 1709-1719) correctly checks 'if (pkt + offset + field_template->total_length > packet_end)' before each iteration. The Data branch omits this check entirely. Since template definitions are sent by the network peer (and are unauthenticated UDP), an attacker can craft templates that cause the parser to read arbitrary memory past the packet buffer. This can leak sensitive memory contents or cause a crash.
References

cve-icon MITRE

Status: PUBLISHED

Assigner: mitre

Published:

Updated: 2026-05-26T20:14:16.692Z

Reserved: 2026-05-22T00:00:00.000Z

Link: CVE-2026-48683

cve-icon Vulnrichment

Updated: 2026-05-26T20:09:56.547Z

cve-icon NVD

Status : Deferred

Published: 2026-05-26T16:16:26.330

Modified: 2026-05-26T21:16:42.023

Link: CVE-2026-48683

cve-icon Redhat

No data.

cve-icon OpenCVE Enrichment

Updated: 2026-05-27T01:00:12Z