---
id: CVE-2026-122130
title: >-
  CESNET ipfixcol2 2.3.0 before 2.9.0 Buffer Overflow via Forwarder Output
  Plugin
summary: >-
  CESNET ipfixcol2 2.3.0 before 2.9.0 contains an integer overflow vulnerability
  in the Forwarder output plugin that allows unauthenticated IPFIX exporters to
  overflow a heap buffer by wrapping uint16_t message length counters. Attackers
  c…
severity: high
cvss: 8.2
cvssVector: 'CVSS:3.1/AV:N/AC:L/PR:N/UI:N/S:U/C:N/I:L/A:H'
cvssSource: cna
cwe:
  - CWE-190
vendor: CESNET
product: ipfixcol2
affected:
  - ipfixcol2 >= 2.3.0 < 2.9.0
ssvc:
  exploitation: none
  automatable: 'yes'
  technicalImpact: partial
  timestamp: '2026-11-05T19:37:16.685325Z'
published: '2026-11-04'
updated: '2026-11-05'
sourceUpdated: '2026-11-05T19:39:01.965Z'
source: CVEORG
sourceUrl: 'https://www.cve.org/CVERecord?id=CVE-2026-122130'
references:
  - url: >-
      https://github.com/CESNET/ipfixcol2/commit/ad206f6217257b06b139f1b2bce50d52f5bc6acb
    label: Patch Commit
  - url: 'https://github.com/CESNET/ipfixcol2'
  - url: 'https://github.com/CESNET/ipfixcol2/releases/tag/v2.9.0'
    label: ipfixcol2 v2.9.0 Release Notes
  - url: >-
      https://github.com/CESNET/ipfixcol2/blob/v2.8.0/src/plugins/output/forwarder/src/Message.cpp#L134-L156
  - url: >-
      https://www.vulncheck.com/advisories/cesnet-ipfixcol2-2.3.0-before-2.9.0-buffer-overflow-via-forwarder-output-plugin
    label: >-
      VulnCheck Advisory: CESNET ipfixcol2 2.3.0 before 2.9.0 Buffer Overflow
      via Forwarder Output Plugin
tags:
  - cve.org
epss: 0.00318
epssPercentile: 0.24867
ingestedAt: '2026-11-05T22:38:31.554Z'
---

## Overview

CESNET ipfixcol2 2.3.0 before 2.9.0 contains an integer overflow vulnerability in the Forwarder output plugin that allows unauthenticated IPFIX exporters to overflow a heap buffer by wrapping uint16_t message length counters. Attackers can send near-65535-byte data sets and large templates to a collector forwarding over TCP to crash it and perform 2-byte writes to attacker-influenced addresses.

## Affected

- `ipfixcol2 >= 2.3.0 < 2.9.0`

## Remediation

Refer to the linked advisories for vendor-supplied fixes and affected version ranges.