---
id: CVE-2026-92693
title: >-
  FastNetMon: IPv6 Fragment header dereferenced without bounds check in shared
  packet parser
summary: >-
  FastNetMon is a high-performance DDoS detector and sensor. In version 1.2.9
  and earlier, parse_raw_packet_to_simple_packet_full() in
  src/simple_packet_parser_ng.cpp dereferences ipv6_extension_header_fragment_t
  when IpProtocolNumberIPV6_…
severity: high
cvss: 8.2
cvssVector: 'CVSS:3.1/AV:N/AC:L/PR:N/UI:N/S:U/C:L/I:N/A:H'
cvssSource: cna
cwe:
  - CWE-125
vendor: pavel-odintsov
product: fastnetmon
affected:
  - fastnetmon <= 1.2.9
ssvc:
  exploitation: poc
  automatable: 'yes'
  technicalImpact: partial
  timestamp: '2026-11-06T17:41:42.515620Z'
exploitAvailable: true
published: '2026-11-05'
updated: '2026-11-06'
sourceUpdated: '2026-11-06T17:42:09.687Z'
source: CVEORG
sourceUrl: 'https://www.cve.org/CVERecord?id=CVE-2026-92693'
references:
  - url: >-
      https://github.com/pavel-odintsov/fastnetmon/security/advisories/GHSA-jmjw-392h-4g93
    label: >-
      https://github.com/pavel-odintsov/fastnetmon/security/advisories/GHSA-jmjw-392h-4g93
  - url: >-
      https://github.com/pavel-odintsov/fastnetmon/commit/1da80df73620c6d0aa4462e9611e65047529b12a
    label: >-
      https://github.com/pavel-odintsov/fastnetmon/commit/1da80df73620c6d0aa4462e9611e65047529b12a
tags:
  - cve.org
  - exploit-available
epss: 0.00258
epssPercentile: 0.17574
ingestedAt: '2026-11-05T23:41:31.943Z'
---

## Overview

FastNetMon is a high-performance DDoS detector and sensor. In version 1.2.9 and earlier, parse_raw_packet_to_simple_packet_full() in src/simple_packet_parser_ng.cpp dereferences ipv6_extension_header_fragment_t when IpProtocolNumberIPV6_FRAG is present without first verifying that the eight-byte Fragment header remains. A crafted sFlow v5 RAW_PACKET_HEADER record can remotely reach this shared parser with the Fragment bytes omitted, causing an unauthenticated remote out-of-bounds read. The supplied harness detects the read under AddressSanitizer, but the advisory does not establish a production process crash. No fixed release is available as of this review.

## Affected

- `fastnetmon <= 1.2.9`

## Remediation

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