Vulnerability Database

346,508

Total vulnerabilities in the database

CVE-2024-21611 — juniper / junos

Missing Release of Memory after Effective Lifetime

A Missing Release of Memory after Effective Lifetime vulnerability in the Routing Protocol Daemon (rpd) of Juniper Networks Junos OS and Junos OS Evolved allows an unauthenticated, network-based attacker to cause a Denial of Service (DoS).

In a Juniper Flow Monitoring (jflow) scenario route churn that causes BGP next hops to be updated will cause a slow memory leak and eventually a crash and restart of rpd.

Thread level memory utilization for the areas where the leak occurs can be checked using the below command:

user@host> show task memory detail | match so_in so_in6 28 32 344450 11022400 344760 11032320 so_in 8 16 1841629 29466064 1841734 29467744 This issue affects:

Junos OS

  • 21.4 versions earlier than 21.4R3;
  • 22.1 versions earlier than 22.1R3;
  • 22.2 versions earlier than 22.2R3.

Junos OS Evolved

  • 21.4-EVO versions earlier than 21.4R3-EVO;
  • 22.1-EVO versions earlier than 22.1R3-EVO;
  • 22.2-EVO versions earlier than 22.2R3-EVO.

This issue does not affect:

Juniper Networks Junos OS versions earlier than 21.4R1.

Juniper Networks Junos OS Evolved versions earlier than 21.4R1.

  • Published: Jan 12, 2024
  • Updated: Nov 16, 2025
  • CVE: CVE-2024-21611
  • 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 21.4-r1-s1 21.4-r1-s1.x
juniper / junos 21.4-r1 21.4-r1.x
juniper / junos 21.4-r1-s2 21.4-r1-s2.x
juniper / junos 22.1-r1 22.1-r1.x
juniper / junos 21.4-r2 21.4-r2.x
juniper / junos 21.4-r2-s1 21.4-r2-s1.x
juniper / junos 21.4 21.4.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 22.1-r2-s2 22.1-r2-s2.x
juniper / junos 21.4-r2-s2 21.4-r2-s2.x
juniper / junos 22.2-r1 22.2-r1.x
juniper / junos 22.2-r1-s1 22.2-r1-s1.x
juniper / junos 22.2-r2 22.2-r2.x
juniper / junos 22.2-r1-s2 22.2-r1-s2.x
juniper / junos 22.2-r2-s1 22.2-r2-s1.x
juniper / junos 22.1-r2-s1 22.1-r2-s1.x
juniper / junos 22.2-r2-s2 22.2-r2-s2.x
juniper / junos 22.2 22.2.x
juniper / junos 22.1 22.1.x
juniper / junos_os_evolved 21.4-r1 21.4-r1.x
juniper / junos_os_evolved 21.4-r1-s1 21.4-r1-s1.x
juniper / junos_os_evolved 21.4 21.4.x
juniper / junos_os_evolved 22.1-r1 22.1-r1.x
juniper / junos_os_evolved 21.4-r2 21.4-r2.x
juniper / junos_os_evolved 21.4-r2-s1 21.4-r2-s1.x
juniper / junos_os_evolved 21.4-r2-s2 21.4-r2-s2.x
juniper / junos_os_evolved 22.1-r1-s1 22.1-r1-s1.x
juniper / junos_os_evolved 22.1-r1-s2 22.1-r1-s2.x
juniper / junos_os_evolved 21.4-r1-s2 21.4-r1-s2.x
juniper / junos_os_evolved 22.2-r1-s1 22.2-r1-s1.x
juniper / junos_os_evolved 22.2-r1 22.2-r1.x
juniper / junos_os_evolved 22.1-r2 22.1-r2.x
juniper / junos_os_evolved 22.2-r2 22.2-r2.x
juniper / junos_os_evolved 22.2-r2-s1 22.2-r2-s1.x
juniper / junos_os_evolved 22.1-r2-s1 22.1-r2-s1.x
juniper / junos_os_evolved 22.2-r2-s2 22.2-r2-s2.x
juniper / junos_os_evolved 22.2 22.2.x
juniper / junos_os_evolved 22.1 22.1.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.