Vulnerability Database

346,508

Total vulnerabilities in the database

CVE-2023-22396 — juniper / junos

Uncontrolled Resource Consumption

An Uncontrolled Resource Consumption vulnerability in TCP processing on the Routing Engine (RE) of Juniper Networks Junos OS allows an unauthenticated network-based attacker to send crafted TCP packets destined to the device, resulting in an MBUF leak that ultimately leads to a Denial of Service (DoS). The system does not recover automatically and must be manually restarted to restore service. This issue occurs when crafted TCP packets are sent directly to a configured IPv4 or IPv6 interface on the device. Transit traffic will not trigger this issue. MBUF usage can be monitored through the use of the 'show system buffers' command. For example: user@junos> show system buffers | refresh 5 4054/566/4620 mbufs in use (current/cache/total) ... 4089/531/4620 mbufs in use (current/cache/total) ... 4151/589/4740 mbufs in use (current/cache/total) ... 4213/527/4740 mbufs in use (current/cache/total) This issue affects Juniper Networks Junos OS: 12.3 version 12.3R12-S19 and later versions; 15.1 version 15.1R7-S10 and later versions; 17.3 version 17.3R3-S12 and later versions; 18.4 version 18.4R3-S9 and later versions; 19.1 version 19.1R3-S7 and later versions; 19.2 version 19.2R3-S3 and later versions; 19.3 version 19.3R2-S7, 19.3R3-S3 and later versions prior to 19.3R3-S7; 19.4 version 19.4R2-S7, 19.4R3-S5 and later versions prior to 19.4R3-S10; 20.1 version 20.1R3-S1 and later versions; 20.2 version 20.2R3-S2 and later versions prior to 20.2R3-S6; 20.3 version 20.3R3-S1 and later versions prior to 20.3R3-S6; 20.4 version 20.4R2-S2, 20.4R3 and later versions prior to 20.4R3-S5; 21.1 version 21.1R2 and later versions prior to 21.1R3-S4; 21.2 version 21.2R1-S1, 21.2R2 and later versions prior to 21.2R3-S3; 21.3 versions prior to 21.3R3-S2; 21.4 versions prior to 21.4R3; 22.1 versions prior to 22.1R2-S1, 22.1R3; 22.2 versions prior to 22.2R1-S2, 22.2R2; 22.3 versions prior to 22.3R1-S1, 22.3R2.

  • Published: Jan 13, 2023
  • Updated: Nov 16, 2025
  • CVE: CVE-2023-22396
  • Severity: High
  • Exploit:

CVSS v3:

  • Severity: High
  • Score: 7.5
  • AV:N/AC:L/PR:N/UI:N/S:U/C:N/I:N/A:H

CWEs:

Software From Fixed in
juniper / junos 19.4-r3-s5 19.4-r3-s5.x
juniper / junos 18.4-r3-s9 18.4-r3-s9.x
juniper / junos 15.1-r7-s10 15.1-r7-s10.x
juniper / junos 20.2-r3-s2 20.2-r3-s2.x
juniper / junos 20.1-r3-s1 20.1-r3-s1.x
juniper / junos 19.3-r3-s3 19.3-r3-s3.x
juniper / junos 19.2-r3-s3 19.2-r3-s3.x
juniper / junos 21.2-r1-s1 21.2-r1-s1.x
juniper / junos 21.1-r2 21.1-r2.x
juniper / junos 12.3-r12-s19 12.3-r12-s19.x
juniper / junos 19.4-r3-s6 19.4-r3-s6.x
juniper / junos 20.4-r3 20.4-r3.x
juniper / junos 18.4-r3-s10 18.4-r3-s10.x
juniper / junos 17.3-r3-s12 17.3-r3-s12.x
juniper / junos 15.1-r7-s11 15.1-r7-s11.x
juniper / junos 19.1-r3-s7 19.1-r3-s7.x
juniper / junos 19.2-r3-s4 19.2-r3-s4.x
juniper / junos 19.3-r3-s4 19.3-r3-s4.x
juniper / junos 20.1-r3-s2 20.1-r3-s2.x
juniper / junos 20.2-r3-s3 20.2-r3-s3.x
juniper / junos 20.3-r3-s1 20.3-r3-s1.x
juniper / junos 21.3-r1 21.3-r1.x
juniper / junos 21.3-r2 21.3-r2.x
juniper / junos 21.2-r2 21.2-r2.x
juniper / junos 20.4-r3-s1 20.4-r3-s1.x
juniper / junos 20.4-r2-s2 20.4-r2-s2.x
juniper / junos 21.1-r3 21.1-r3.x
juniper / junos 21.1-r2-s1 21.1-r2-s1.x
juniper / junos 21.1-r2-s2 21.1-r2-s2.x
juniper / junos 21.2-r2-s1 21.2-r2-s1.x
juniper / junos 20.1-r3-s3 20.1-r3-s3.x
juniper / junos 21.2-r2-s2 21.2-r2-s2.x
juniper / junos 21.4-r1-s1 21.4-r1-s1.x
juniper / junos 21.3-r1-s1 21.3-r1-s1.x
juniper / junos 21.3-r1-s2 21.3-r1-s2.x
juniper / junos 21.4-r1 21.4-r1.x
juniper / junos 19.2-r3-s5 19.2-r3-s5.x
juniper / junos 18.4-r3-s11 18.4-r3-s11.x
juniper / junos 20.3-r3-s2 20.3-r3-s2.x
juniper / junos 21.3-r2-s1 21.3-r2-s1.x
juniper / junos 21.3-r2-s2 21.3-r2-s2.x
juniper / junos 21.4-r1-s2 21.4-r1-s2.x
juniper / junos 19.1-r3-s8 19.1-r3-s8.x
juniper / junos 19.3-r3-s5 19.3-r3-s5.x
juniper / junos 19.4-r3-s7 19.4-r3-s7.x
juniper / junos 20.2-r3-s4 20.2-r3-s4.x
juniper / junos 20.3-r3-s3 20.3-r3-s3.x
juniper / junos 20.4-r3-s2 20.4-r3-s2.x
juniper / junos 21.1-r3-s1 21.1-r3-s1.x
juniper / junos 21.2-r3 21.2-r3.x
juniper / junos 22.1-r1 22.1-r1.x
juniper / junos 21.3-r3 21.3-r3.x
juniper / junos 21.3-r3-s1 21.3-r3-s1.x
juniper / junos 21.4-r2 21.4-r2.x
juniper / junos 21.4-r2-s1 21.4-r2-s1.x
juniper / junos 20.4-r3-s3 20.4-r3-s3.x
juniper / junos 12.3-r12-s20 12.3-r12-s20.x
juniper / junos 15.1-r7-s12 15.1-r7-s12.x
juniper / junos 21.4 21.4.x
juniper / junos 21.3 21.3.x
juniper / junos 21.1-r3-s2 21.1-r3-s2.x
juniper / junos 22.1-r1-s1 22.1-r1-s1.x
juniper / junos 22.1-r2 22.1-r2.x
juniper / junos 22.1-r1-s2 22.1-r1-s2.x
juniper / junos 21.4-r2-s2 21.4-r2-s2.x
juniper / junos 20.3-r3-s5 20.3-r3-s5.x
juniper / junos 20.1-r3-s4 20.1-r3-s4.x
juniper / junos 19.4-r3-s8 19.4-r3-s8.x
juniper / junos 20.3-r3-s4 20.3-r3-s4.x
juniper / junos 19.3-r3-s6 19.3-r3-s6.x
juniper / junos 19.4 19.4.x
juniper / junos 22.2-r1 22.2-r1.x
juniper / junos 22.2-r1-s1 22.2-r1-s1.x
juniper / junos 20.4-r3-s4 20.4-r3-s4.x
juniper / junos 21.2-r3-s2 21.2-r3-s2.x
juniper / junos 19.4-r2-s7 19.4-r2-s7.x
juniper / junos 21.2-r3-s1 21.2-r3-s1.x
juniper / junos 22.3-r1 22.3-r1.x
juniper / junos 21.1-r3-s3 21.1-r3-s3.x
juniper / junos 22.2-r2 22.2-r2.x
juniper / junos 20.2-r3-s5 20.2-r3-s5.x
juniper / junos 19.4-r3-s9 19.4-r3-s9.x
juniper / junos 22.3-r2 22.3-r2.x
juniper / junos 22.1-r3 22.1-r3.x
juniper / junos 20.4-r3-s5 20.4-r3-s5.x
juniper / junos 19.3-r2-s7 19.3-r2-s7.x

Frequently Asked Questions

A security vulnerability is a weakness in software, hardware, or configuration that can be exploited to compromise confidentiality, integrity, or availability. Many vulnerabilities are tracked as CVEs (Common Vulnerabilities and Exposures), which provide a standardized identifier so teams can coordinate patching, mitigation, and risk assessment across tools and vendors.

CVSS (Common Vulnerability Scoring System) estimates technical severity, but it doesn't automatically equal business risk. Prioritize using context like internet exposure, affected asset criticality, known exploitation (proof-of-concept or in-the-wild), and whether compensating controls exist. A "Medium" CVSS on an exposed, production system can be more urgent than a "Critical" on an isolated, non-production host.

A vulnerability is the underlying weakness. An exploit is the method or code used to take advantage of it. A zero-day is a vulnerability that is unknown to the vendor or has no publicly available fix when attackers begin using it. In practice, risk increases sharply when exploitation becomes reliable or widespread.

Recurring findings usually come from incomplete Asset Discovery, inconsistent patch management, inherited images, and configuration drift. In modern environments, you also need to watch the software supply chain: dependencies, containers, build pipelines, and third-party services can reintroduce the same weakness even after you patch a single host. Unknown or unmanaged assets (often called Shadow IT) are a common reason the same issues resurface.

Use a simple, repeatable triage model: focus first on externally exposed assets, high-value systems (identity, VPN, email, production), vulnerabilities with known exploits, and issues that enable remote code execution or privilege escalation. Then enforce patch SLAs and track progress using consistent metrics so remediation is steady, not reactive.

SynScan combines attack surface monitoring and continuous security auditing to keep your inventory current, flag high-impact vulnerabilities early, and help you turn raw findings into a practical remediation plan.