CVE-2023-44199: Juniper Junos

High severity, CVSS 7.5. EPSS: 0.5% chance of exploitation in the next 30 days.

An Improper Check for Unusual or Exceptional Conditions vulnerability in the Packet Forwarding Engine (PFE) of Juniper Networks Junos OS on MX Series allows a network-based, unauthenticated attacker to cause a Denial of Service (DoS). On Junos MX Series platforms with Precision Time Protocol (PTP) configured, a prolonged routing protocol churn can lead to an FPC crash and restart. This issue affects Juniper Networks Junos OS on MX Series: * All versions prior to 20.4R3-S4; * 21.1 version 21.1R1 and later versions; * 21.2 versions prior to 21.2R3-S2; * 21.3 versions prior to 21.3R3-S5; * 21.4 versions prior to 21.4R3; * 22.1 versions prior to 22.1R3; * 22.2 versions prior to 22.2R1-S1, 22.2R2.

Affected products

  • Juniper Junos: before 20.4 (fixed in 20.4); version 20.4 only; version 21.1 only; version 21.2 only; version 21.3 only; version 21.4 only; …

Published 2023-10-13. Last modified 2026-06-17.