---
id: CVE-2026-102178
title: >-
  A Stack-based Buffer Overflow vulnerability in the BGP routing daemon of
  Juniper Networks Junos OS and Junos OS Evolved allows a configured BGP
  flowspec peer to cause routing-engine compromise or a routing-daemon denial of
  service via fl…
summary: >-
  A Stack-based Buffer Overflow vulnerability in the BGP routing daemon of
  Juniper Networks Junos OS and Junos OS Evolved allows a configured BGP
  flowspec peer to cause routing-engine compromise or a routing-daemon denial of
  service via fl…
severity: critical
cvss: 9.8
cvssVector: 'CVSS:3.1/AV:N/AC:L/PR:N/UI:N/S:U/C:H/I:H/A:H'
cwe:
  - CWE-121
vendor: Juniper Networks
product: Junos OS
affected:
  - junos_os < 23.2R2-S7.7
  - junos_os >= 23.4 < 23.4R2-S8.13
  - junos_os >= 24.2 < 24.2R2-S5.5
  - junos_os >= 24.4 < 24.4R2-S5
  - junos_os >= 25.2 < 25.2R2-S2
  - junos_os >= 25.4 < 25.4R1-S3
  - junos_os >= 26.2 < 26.2R1-S2
  - junos_os_evolved < 23.2R2-S7.7-EVO
  - junos_os_evolved >= 23.4 < 23.4R2-S8.11-EVO
  - junos_os_evolved >= 24.2 < 24.2R2-S5.6-EVO
  - junos_os_evolved >= 24.4 < 24.4R2-S5-EVO
  - junos_os_evolved >= 25.2 < 25.2R2-S2-EVO
  - junos_os_evolved >= 25.4 < 25.4R1-S3-EVO
  - junos_os_evolved >= 26.2 < 26.2R1-S2-EVO
  - junos_os_evolved 23.4X100
  - junos_os_evolved >= 25.2X100 < 25.2X100-D35-EVO
  - junos_os_evolved >= 25.4X300 < 25.4X300-D40-EVO
published: '2026-10-14'
updated: '2026-10-16'
sourceUpdated: '2026-10-16T17:17:10.237'
source: NVD
sourceUrl: 'https://nvd.nist.gov/vuln/detail/CVE-2026-102178'
references:
  - url: 'https://supportportal.juniper.net/JSA112187'
    label: sirt@juniper.net
tags:
  - nvd
  - cve.org
epss: 0.00455
epssPercentile: 0.39297
ssvc:
  exploitation: none
  automatable: 'yes'
  technicalImpact: total
  timestamp: '2026-10-16T16:35:30.334189Z'
ingestedAt: '2026-10-14T17:44:53.669Z'
---

## Overview

A Stack-based Buffer Overflow vulnerability in the BGP routing daemon of Juniper Networks Junos OS and Junos OS Evolved allows a configured BGP flowspec peer to cause routing-engine compromise or a routing-daemon denial of service via flowspec route re-advertisement when BGP update-threading is enabled.

## Remediation

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