Out-of-bounds write in Junos OS and Junos OS Evolved - CVE-2026-33799
Published: July 8, 2026
Vulnerability identifier: #VU137150
CSH Severity: Medium
CVSS v4: 8.7 [CVSS:4.0/AV:N/AC:L/AT:N/PR:N/UI:N/VC:N/VI:N/VA:H/SC:N/SI:N/SA:N]
CVE-ID: CVE-2026-33799
CWE-ID: CWE-787
Exploitation vector: Remote access
Exploit availability:
No public exploit available
Vulnerability details
The vulnerability allows a remote attacker to cause a denial of service.
The vulnerability exists due to out-of-bounds write in the SNMP daemon (snmpd) when processing specific valid SNMPv3 queries. A remote attacker can send specific valid SNMPv3 queries to cause a denial of service.
SNMPv3 must be configured for exploitation. Continuous receipt of the queries can exhaust snmpd process memory, leading to a crash and restart and impacting SNMP-based monitoring.
Affected software
Junos OS
Junos OS Evolved
Junos OS Evolved
How to mitigate CVE-2026-33799
Install security update from vendor's website.
Junos OS - addressed in versions 21.2R3-S8, 21.4R3-S7, 22.1R3-S6, 22.2R3-S4, 22.3R3-S3, 22.4R3-S2, 23.2R2, 23.4R2, 24.2R1
Junos OS Evolved - addressed in versions 21.2R3-S8-EVO, 21.4R3-S7-EVO, 22.2R3-S4-EVO, 22.3R3-S3-EVO, 23.2R2-EVO, 23.4R2-EVO, 24.2R1-EVO
Junos OS Evolved - addressed in versions 21.2R3-S8-EVO, 21.4R3-S7-EVO, 22.2R3-S4-EVO, 22.3R3-S3-EVO, 23.2R2-EVO, 23.4R2-EVO, 24.2R1-EVO