Improper Check for Unusual or Exceptional Conditions in Junos OS - CVE-2026-33790
Published: May 8, 2026
Vulnerability identifier: #VU130698
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-2026-33790
CWE-ID: CWE-754
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 improper check for unusual or exceptional conditions in the flow daemon (flowd) when processing a specific malformed ICMPv6 packet during NAT64 translation. A remote attacker can send a specially crafted ICMPv6 packet to cause a denial of service.
This issue requires a NAT64 configuration to be present and cannot be triggered using IPv4 or other IPv6 traffic.
Affected software
Junos OS
How to mitigate CVE-2026-33790
Install security update from vendor's website.
Junos OS - addressed in versions 21.2R3-S10, 21.4R3-S12, 22.4R3-S9, 23.2R2-S6, 23.4R2-S7, 24.2R2-S3, 24.4R2-S3, 25.2R1-S2, 25.2R2, 25.4R1