---
id: CVE-2026-93345
title: >-
  MikroTik RouterOS before 7.25beta4 contains an improper input validation
  vulnerability in the labelled-VPN NLRI iterators of the routing service that
  allows an unauthenticated on-path attacker to crash the BGP service by sending
  a malfor…
summary: >-
  MikroTik RouterOS before 7.25beta4 contains an improper input validation
  vulnerability in the labelled-VPN NLRI iterators of the routing service that
  allows an unauthenticated on-path attacker to crash the BGP service by sending
  a malfor…
severity: high
cvss: 7.5
cvssVector: 'CVSS:3.1/AV:N/AC:L/PR:N/UI:N/S:U/C:N/I:N/A:H'
cwe:
  - CWE-1284
vendor: MikroTik
product: RouterOS
affected:
  - RouterOS >= 7.21.5 < 7.25beta4
published: '2026-09-22'
updated: '2026-09-22'
sourceUpdated: '2026-09-22T20:25:55.870'
source: NVD
sourceUrl: 'https://nvd.nist.gov/vuln/detail/CVE-2026-93345'
references:
  - url: 'https://forum.mikrotik.com/t/7-25beta-development-is-released/272788'
    label: disclosure@vulncheck.com
  - url: >-
      https://www.vulncheck.com/advisories/mikrotik-routeros-improper-input-validation-dos-via-bgp-labelled-vpn-nlri
    label: disclosure@vulncheck.com
tags:
  - nvd
  - cve.org
ssvc:
  exploitation: none
  automatable: 'yes'
  technicalImpact: partial
  timestamp: '2026-09-22T18:26:08.433636Z'
ingestedAt: '2026-09-22T18:08:12.501Z'
epss: 0.00488
epssPercentile: 0.41107
---

## Overview

MikroTik RouterOS before 7.25beta4 contains an improper input validation vulnerability in the labelled-VPN NLRI iterators of the routing service that allows an unauthenticated on-path attacker to crash the BGP service by sending a malformed MP_REACH_NLRI UPDATE message with a prefix-length value below the minimum valid for a labelled-VPN NLRI, which passes validation while describing a route with a negative-length address portion. Attackers can repeatedly send a single BGP UPDATE packet carrying a VPNv4 or VPNv6 NLRI with an out-of-bounds prefix-length to indefinitely hold down the BGP plane, causing session termination without a NOTIFICATION and triggering a service malfunction on the device.

## Remediation

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