---
id: CVE-2026-101955
title: >-
  A Stack-based Buffer Overflow vulnerability in the UTM Anti-Spam SBL of
  Juniper Networks Junos OS on SRX series allows an unauthenticated remote
  attacker to cause arbitrary code execution or a denial of service via a
  injected malformed D…
summary: >-
  A Stack-based Buffer Overflow vulnerability in the UTM Anti-Spam SBL of
  Juniper Networks Junos OS on SRX series allows an unauthenticated remote
  attacker to cause arbitrary code execution or a denial of service via a
  injected malformed D…
severity: high
cvss: 8.1
cvssVector: 'CVSS:3.1/AV:N/AC:H/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
published: '2026-10-14'
updated: '2026-10-16'
sourceUpdated: '2026-10-16T15:16:59.440'
source: NVD
sourceUrl: 'https://nvd.nist.gov/vuln/detail/CVE-2026-101955'
references:
  - url: 'https://supportportal.juniper.net/JSA112186'
    label: sirt@juniper.net
tags:
  - nvd
  - cve.org
epss: 0.00529
epssPercentile: 0.44535
ssvc:
  exploitation: none
  automatable: 'no'
  technicalImpact: total
  timestamp: '2026-10-16T03:56:35.048614Z'
ingestedAt: '2026-10-14T17:44:53.631Z'
---

## Overview

A Stack-based Buffer Overflow vulnerability in the UTM Anti-Spam SBL of Juniper Networks Junos OS on SRX series allows an unauthenticated remote attacker to cause arbitrary code execution or a denial of service via a injected malformed DNS packet when Anti-Spam SBL inspection is enabled.

## Remediation

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