High7.5Juniper Networks

High [CVE-2026-33790] Improper Check for Unusual or Exceptional Conditions vulnerability in the flow daemon (flowd) of Juniper Networks Junos OS on SRX Series allows an attacker sending a specific, malformed ICMPv6 packet to cause the srxpfe process to crash and restart

This high-severity Juniper Networks advisory covers CVE-2026-33790 affecting Junos OS, Junos, SRX.

CVE-2026-33790 Published Apr 9, 2026Updated by vendor Jun 17, 2026

CVE-2026-33790

Affected products & platforms

Juniper NetworksSRXFirewallJunos

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Summary

An Improper Check for Unusual or Exceptional Conditions vulnerability in the flow daemon (flowd) of Juniper Networks Junos OS on SRX Series allows an attacker sending a specific, malformed ICMPv6 packet to cause the srxpfe process to crash and restart.

Continued receipt and processing of these packets will repeatedly crash the srxpfe process and sustain the Denial of Service (DoS) condition.

During NAT64 translation, receipt of a specific, malformed ICMPv6 packet destined to the device will cause the srxpfe process to crash and restart.

This issue cannot be triggered using IPv4 nor other IPv6 traffic.

This issue affects Junos OS on SRX Series:

all versions before 21.2R3-S10,
from 21.4 before 21.4R3-S12,
from 23.2 before 23.2R2-S6,
from 23.4 before 23.4R2-S7,

Affected versions

* all versions before 21

Official advisory · high-confidence parse· fetched 2 months ago·verify at source

Fixed versions

21.2R3-S10
21.4R3-S12
22.2R3-S8
22.4R3-S9
23.2R2-S6
23.4R2-S7
24.2R2-S3
24.4R2-S3
25.2R1-S2

Official advisory · high-confidence parse· fetched 2 months ago·verify at source

Mitigation

Upgrade to a fixed release: 21.2R3-S10, 21.4R3-S12, 22.2R3-S8, 22.4R3-S9, 23.2R2-S6, 23.4R2-S7. That is the remediation for this advisory.

The vendor advisory may list additional interim mitigations or workarounds not captured here — review it before change work.

Official advisory · high-confidence parse· fetched 2 months ago·verify at source

Sources

Official and corroborating records used to build this advisory.

NVD discovery recordNVD
Independent discovery and scoring cross-reference. Vendor remediation guidance takes precedence. Discovered from the machine-readable feed https://services.nvd.nist.gov/rest/json/cves/2.0; this link opens the NVD record for CVE-2026-33790 instead of the raw feed document.
NIST National Vulnerability Database

Cross-references

Validate CVE metadata against the authoritative registries.

CVE-2026-33790NVD CVE.org MITRE

Official resources

Junos OS software downloads & install/upgrade (target: 21.2R3-S10 / 21.4R3-S12 / 22.2R3-S8)
Official documentation
This advisory names 21.2R3-S10 / 21.4R3-S12 / 22.2R3-S8 as the first fixed releases — official upgrade documentation for Junos OS on SRX / MX / EX / QFX.
Junos OS release & EOL / support dates
Release notes
Confirm your train is still supported and pick a fixed maintenance release.
Juniper Security Advisories portal
Official documentation
Canonical Juniper SIRT advisory portal — search here for the full JSA text and revisions.

Discussion(0)

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