CVE-2026-33799Network attack vector

SNMP monitoring interruption via snmpd memory exhaustion

Published Jul 9, 2026 · Updated Jul 9, 2026

Out-of-bounds write in snmpd in Juniper Networks Junos OS and Junos OS Evolved allows remote authenticated users to crash the daemon. Specific valid SNMPv3 queries make snmpd retain memory instead of releasing it, and repeated requests exhaust the process memory. SNMPv3 credentials and sustained network access are required; the crash triggers an automatic restart and interrupts SNMP monitoring.

CVSS severity5.3
Medium
EPSS probability0.37%
Next 30 days · Sep 16, 2026
Known exploitationUnconfirmed
Based on sourced intelligence
Hinoki checkNot available
Coverage for this vulnerability

See if you're affected

Explore vulnerability checks for your environment with Hinoki.

Book a demo

Summary

What happened

Out-of-bounds write in snmpd in Juniper Networks Junos OS and Junos OS Evolved allows remote authenticated users to crash the daemon. Specific valid SNMPv3 queries make snmpd retain memory instead of releasing it, and repeated requests exhaust the process memory. SNMPv3 credentials and sustained network access are required; the crash triggers an automatic restart and interrupts SNMP monitoring.

The record

CVE
CVE-2026-33799
Published
Jul 9, 2026
Updated
Jul 9, 2026
Vendor
Juniper Networks
Product
Junos OS Evolved
Classifications
CWE-787, T1499.002
Attack vector
network
Privileges
authenticated

Timeline

How it unfolded

  1. Jul 9, 2026CVE publishedPublication date reported by the CVE source.
  2. Jul 9, 2026Record updatedLatest update available in the CVE record.

Exploitability

Present is not the same as exploitable

Compare your product and version with the public record. A matching version still requires validation against your environment.

Is a vulnerable build present?

Compare these published version ranges with your installed build and any vendor patches.

  1. Affected versionversion=0 <21.2R3-S8-EVO
  2. Affected versionversion=21.4 <21.4R3-S7-EVO
  3. Affected versionversion=22.1 <22.1*
  4. Affected versionversion=22.2 <22.2R3-S4-EVO
  5. Affected versionversion=22.3 <22.3R3-S3-EVO
  6. Affected versionversion=22.4 <22.4*
  7. Affected versionversion=23.2 <23.2R2-EVO
  8. Affected versionversion=23.4 <23.4R2-EVO

What conditions does exploitation require?

Attack vectornetwork
Required privilegesauthenticated

What is affected?

Juniper Networks · Junos OS Evolvedversion=0 <21.2R3-S8-EVO; version=21.4 <21.4R3-S7-EVO; version=22.1 <22.1*; version=22.2 <22.2R3-S4-EVO; version=22.3 <22.3R3-S3-EVO; version=22.4 <22.4*; version=23.2 <23.2R2-EVO; version=23.4 <23.4R2-EVO
Juniper Networks · Junos OSversion=0 <21.2R3-S8; version=21.4 <21.4R3-S7; version=22.1 <22.1R3-S6; version=22.2 <22.2R3-S4; version=22.3 <22.3R3-S3; version=22.4 <22.4R3-S2; version=23.2 <23.2R2; version=23.4 <23.4R2

Published CVSS scores

4.3Juniper NetworksCVSS:3.1/AV:N/AC:L/PR:L/UI:N/S:U/C:N/I:N/A:L
5.3Juniper NetworksCVSS:4.0/AV:N/AC:L/AT:N/PR:L/UI:N/VC:N/VI:N/VA:L/SC:N/SI:N/SA:N

CVSS describes severity. EPSS estimates exploitation probability.

Attacks

What attackers are doing with it

Daily unique IPs observed by Shadowserver honeypots for known exploited vulnerabilities (KEVs). Missing observations do not establish an absence of attacks.

Daily unique IPsNo honeypot observations are available for this CVE in the selected window.

No observations available

Sep 10, 2026Sep 16, 2026
Latest reporting daySep 16, 2026
Latest daily unique IPsUnavailable
Prior 30-day averageUnavailable
SourceShadowserver honeypots (KEV)
Vectornetwork
Privilegesauthenticated
Known exploitationUnconfirmed
Public exploitUnconfirmed

Weakness, pattern, technique

CWE-787Out-of-bounds Write
T1499.002Service Exhaustion Flood

Public exploit references

No public exploit references are available in this record.

Labels summarize the accepted research assessment. They do not indicate a test against your environment.

Technologies

Your stack

See the directory against your own environment.

Your stack

Check the software in your environment

Book a demo to see how Hinoki identifies affected software and validates exploitability in your environment.

Book a demo