CVE-2026-101955

High

Description

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.

SeverityHigh
CVSS8.1
Exploit probability—
ProductJunos OS
PublishedOct 14, 2026
First seenOct 14, 2026
Weakness typeCWE-121CWE-121

How to fix

Update
  • Juniper Networks Junos OS23.2R2-S7.7, 23.4R2-S8.13, 24.2R2-S5.5, 24.4R2-S5, 25.2R2-S2, 25.4R1-S3, 26.2R1-S2 or later

Affected products

ProductAffected versionsFixed in
Juniper Networks Junos OSv < 23.2R2-S7.7, 23.4 ≤ v < 23.4R2-S8.13, 24.2 ≤ v < 24.2R2-S5.5, 24.4 ≤ v < 24.4R2-S5, 25.2 ≤ v < 25.2R2-S2, 25.4 ≤ v < 25.4R1-S3, 26.2 ≤ v < 26.2R1-S223.2R2-S7.7, 23.4R2-S8.13, 24.2R2-S5.5, 24.4R2-S5, 25.2R2-S2, 25.4R1-S3, 26.2R1-S2

Check your version

Choose the product and enter the version you run to see whether it falls in the affected range.

In the Intelligence 360 plan

Attack Surface Management

See the assets tied to your domains, the technologies they run and known vulnerabilities in one list.

CVE-2026-101955 · Junos OS · Dark Radar