Vulnerability Database

357,869

Total vulnerabilities in the database

CVE-2026-33799 — juniper / junos

Out-of-bounds Write

An Out-of-bounds Write vulnerability in the SNMP daemon (snmpd) of Juniper Networks Junos OS and Junos OS Evolved allows an authenticated network-based attacker sending specific valid SNMPv3 queries to trigger a memory leak. Over time, continuous receipt of these queries will result in snmpd process memory exhaustion, resulting in a process crash and restart, impacting the ability to monitor the system via SNMP.

Memory usage can be monitored using the following command:

user@device> show system processes extensive | match snmpd

This issue affects:

Junos OS:

  • all versions before 21.2R3-S8;
  • from 21.4 before 21.4R3-S7;
  • from 22.1 before 22.1R3-S6;
  • from 22.2 before 22.2R3-S4;
  • from 22.3 before 22.3R3-S3;
  • from 22.4 before 22.4R3-S2;
  • from 23.2 before 23.2R2;
  • from 23.4 before 23.4R2.

Junos OS Evolved:

  • all versions before 21.2R3-S8-EVO;
  • from 21.4 before 21.4R3-S7-EVO;
  • all versions of 22.1-EVO,
  • from 22.2 before 22.2R3-S4-EVO;
  • from 22.3 before 22.3R3-S3-EVO;
  • all versions of 22.4-EVO,
  • from 23.2 before 23.2R2-EVO;
  • from 23.4 before 23.4R2-EVO.
  • Published: Jul 9, 2026
  • Updated: Jul 10, 2026
  • CVE: CVE-2026-33799
  • Severity: Low
  • Exploit:
  • CISA KEV:

CVSS v3:

  • Severity: Low
  • Score: 4.3
  • AV:N/AC:L/PR:L/UI:N/S:U/C:N/I:N/A:L

CWEs:

Software From Fixed in
juniper / junos - 21.2
juniper / junos 21.2 21.2.x
juniper / junos 21.2-r1 21.2-r1.x
juniper / junos 21.2-r1-s1 21.2-r1-s1.x
juniper / junos 21.2-r1-s2 21.2-r1-s2.x
juniper / junos 21.2-r2 21.2-r2.x
juniper / junos 21.2-r2-s1 21.2-r2-s1.x
juniper / junos 21.2-r2-s2 21.2-r2-s2.x
juniper / junos 21.2-r3 21.2-r3.x
juniper / junos 21.2-r3-s1 21.2-r3-s1.x
juniper / junos 21.2-r3-s2 21.2-r3-s2.x
juniper / junos 21.2-r3-s3 21.2-r3-s3.x
juniper / junos 21.2-r3-s4 21.2-r3-s4.x
juniper / junos 21.2-r3-s5 21.2-r3-s5.x
juniper / junos 21.2-r3-s6 21.2-r3-s6.x
juniper / junos 21.2-r3-s7 21.2-r3-s7.x
juniper / junos 21.4 21.4.x
juniper / junos 21.4-r1 21.4-r1.x
juniper / junos 21.4-r1-s1 21.4-r1-s1.x
juniper / junos 21.4-r1-s2 21.4-r1-s2.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-r2-s2 21.4-r2-s2.x
juniper / junos 21.4-r3 21.4-r3.x
juniper / junos 21.4-r3-s1 21.4-r3-s1.x
juniper / junos 21.4-r3-s2 21.4-r3-s2.x
juniper / junos 21.4-r3-s3 21.4-r3-s3.x
juniper / junos 21.4-r3-s4 21.4-r3-s4.x
juniper / junos 21.4-r3-s5 21.4-r3-s5.x
juniper / junos 21.4-r3-s6 21.4-r3-s6.x
juniper / junos 22.1 22.1.x
juniper / junos 22.1-r1 22.1-r1.x
juniper / junos 22.1-r1-s1 22.1-r1-s1.x
juniper / junos 22.1-r1-s2 22.1-r1-s2.x
juniper / junos 22.1-r2 22.1-r2.x
juniper / junos 22.1-r2-s1 22.1-r2-s1.x
juniper / junos 22.1-r2-s2 22.1-r2-s2.x
juniper / junos 22.1-r3 22.1-r3.x
juniper / junos 22.1-r3-s1 22.1-r3-s1.x
juniper / junos 22.1-r3-s2 22.1-r3-s2.x
juniper / junos 22.1-r3-s3 22.1-r3-s3.x
juniper / junos 22.1-r3-s4 22.1-r3-s4.x
juniper / junos 22.1-r3-s5 22.1-r3-s5.x
juniper / junos 22.2 22.2.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-r1-s2 22.2-r1-s2.x
juniper / junos 22.2-r2 22.2-r2.x
juniper / junos 22.2-r2-s1 22.2-r2-s1.x
juniper / junos 22.2-r2-s2 22.2-r2-s2.x
juniper / junos 22.2-r3 22.2-r3.x
juniper / junos 22.2-r3-s1 22.2-r3-s1.x
juniper / junos 22.2-r3-s2 22.2-r3-s2.x
juniper / junos 22.2-r3-s3 22.2-r3-s3.x
juniper / junos 22.3 22.3.x
juniper / junos 22.3-r1 22.3-r1.x
juniper / junos 22.3-r1-s1 22.3-r1-s1.x
juniper / junos 22.3-r1-s2 22.3-r1-s2.x
juniper / junos 22.3-r2 22.3-r2.x
juniper / junos 22.3-r2-s2 22.3-r2-s2.x
juniper / junos 22.3-r3 22.3-r3.x
juniper / junos 22.3-r3-s1 22.3-r3-s1.x
juniper / junos 22.3-r3-s2 22.3-r3-s2.x
juniper / junos 22.4 22.4.x
juniper / junos 22.4-r1 22.4-r1.x
juniper / junos 22.4-r1-s1 22.4-r1-s1.x
juniper / junos 22.4-r1-s2 22.4-r1-s2.x
juniper / junos 22.4-r2 22.4-r2.x
juniper / junos 22.4-r2-s1 22.4-r2-s1.x
juniper / junos 22.4-r2-s2 22.4-r2-s2.x
juniper / junos 22.4-r3 22.4-r3.x
juniper / junos 22.4-r3-s1 22.4-r3-s1.x
juniper / junos 23.2 23.2.x
juniper / junos 23.2-r1 23.2-r1.x
juniper / junos 23.2-r1-s1 23.2-r1-s1.x
juniper / junos 23.2-r1-s2 23.2-r1-s2.x
juniper / junos 23.4 23.4.x
juniper / junos 23.4-r1 23.4-r1.x
juniper / junos 23.4-r1-s1 23.4-r1-s1.x
juniper / junos 23.4-r1-s2 23.4-r1-s2.x
juniper / junos_os_evolved - 21.2
juniper / junos_os_evolved 21.2 21.2.x
juniper / junos_os_evolved 21.2-r1 21.2-r1.x
juniper / junos_os_evolved 21.2-r1-s1 21.2-r1-s1.x
juniper / junos_os_evolved 21.2-r1-s2 21.2-r1-s2.x
juniper / junos_os_evolved 21.2-r2 21.2-r2.x
juniper / junos_os_evolved 21.2-r2-s1 21.2-r2-s1.x
juniper / junos_os_evolved 21.2-r2-s2 21.2-r2-s2.x
juniper / junos_os_evolved 21.2-r3 21.2-r3.x
juniper / junos_os_evolved 21.2-r3-s1 21.2-r3-s1.x
juniper / junos_os_evolved 21.2-r3-s2 21.2-r3-s2.x
juniper / junos_os_evolved 21.2-r3-s3 21.2-r3-s3.x
juniper / junos_os_evolved 21.2-r3-s4 21.2-r3-s4.x
juniper / junos_os_evolved 21.2-r3-s5 21.2-r3-s5.x
juniper / junos_os_evolved 21.2-r3-s6 21.2-r3-s6.x
juniper / junos_os_evolved 21.2-r3-s7 21.2-r3-s7.x
juniper / junos_os_evolved 21.4 21.4.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-r1-s2 21.4-r1-s2.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 21.4-r3 21.4-r3.x
juniper / junos_os_evolved 21.4-r3-s1 21.4-r3-s1.x
juniper / junos_os_evolved 21.4-r3-s2 21.4-r3-s2.x
juniper / junos_os_evolved 21.4-r3-s3 21.4-r3-s3.x
juniper / junos_os_evolved 21.4-r3-s4 21.4-r3-s4.x
juniper / junos_os_evolved 21.4-r3-s5 21.4-r3-s5.x
juniper / junos_os_evolved 21.4-r3-s6 21.4-r3-s6.x
juniper / junos_os_evolved 22.1 22.1.x
juniper / junos_os_evolved 22.2 22.2.x
juniper / junos_os_evolved 22.2-r1 22.2-r1.x
juniper / junos_os_evolved 22.2-r1-s1 22.2-r1-s1.x
juniper / junos_os_evolved 22.2-r1-s2 22.2-r1-s2.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 22.2-r2-s2 22.2-r2-s2.x
juniper / junos_os_evolved 22.2-r3 22.2-r3.x
juniper / junos_os_evolved 22.2-r3-s1 22.2-r3-s1.x
juniper / junos_os_evolved 22.2-r3-s2 22.2-r3-s2.x
juniper / junos_os_evolved 22.2-r3-s3 22.2-r3-s3.x
juniper / junos_os_evolved 22.3 22.3.x
juniper / junos_os_evolved 22.3-r1 22.3-r1.x
juniper / junos_os_evolved 22.3-r1-s1 22.3-r1-s1.x
juniper / junos_os_evolved 22.3-r1-s2 22.3-r1-s2.x
juniper / junos_os_evolved 22.3-r2 22.3-r2.x
juniper / junos_os_evolved 22.3-r2-s2 22.3-r2-s2.x
juniper / junos_os_evolved 22.3-r3 22.3-r3.x
juniper / junos_os_evolved 22.3-r3-s1 22.3-r3-s1.x
juniper / junos_os_evolved 22.3-r3-s2 22.3-r3-s2.x
juniper / junos_os_evolved 22.4 22.4.x
juniper / junos_os_evolved 23.2 23.2.x
juniper / junos_os_evolved 23.2-r1 23.2-r1.x
juniper / junos_os_evolved 23.2-r1-s1 23.2-r1-s1.x
juniper / junos_os_evolved 23.2-r1-s2 23.2-r1-s2.x
juniper / junos_os_evolved 23.4 23.4.x
juniper / junos_os_evolved 23.4-r1 23.4-r1.x
juniper / junos_os_evolved 23.4-r1-s1 23.4-r1-s1.x
juniper / junos_os_evolved 23.4-r1-s2 23.4-r1-s2.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.