CVE-2026-33799

What it is

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.

At a glance

Exploitability

Can be exploited over the network with a low-privilege account. Limited direct impact.

Exploit odds

0.4% chance of exploitation in the next 30 days (EPSS).

Fix

A patch, advisory or fixed version is referenced. Upgrade or apply it.

Timeline

1. 2026-07-09 21:16 UTC PublishedDisclosed publicly on CVE.org and NVD
2. 2026-07-13 12:55 UTC Last updatedMost recent change to the record

Details

Published

2026-07-09 21:16 UTC

Last modified

2026-07-13 12:55 UTC

Exploit probability

0.4% · EPSS, next 30 days

Weakness

CWE-787 · Out-of-bounds write

Record status

Analyzed

Affected

• Juniper Junos < 21.2
• Juniper Junos 21.2
• Juniper Junos 21.4
• Juniper Junos 22.1
• Juniper Junos 22.2
• Juniper Junos 22.3
• Juniper Junos 22.4
• Juniper Junos 23.2

Attack profile CVSS 4.0 · 5.3

Attack vector

Network

Complexity

Low

Attack requirements

None

Privileges needed

Low

User interaction

None

Confidentiality

None

Integrity

None

Availability

Low