CVE-2023-36835

Technical Description

An Improper Check for Unusual or Exceptional Conditions vulnerability in the Packet Forwarding Engine (PFE) of Juniper Networks Junos OS on QFX10000 Series allows a network based attacker to cause a Denial of Service (DoS).

If a specific valid IP packet is received and that packet needs to be routed over a VXLAN tunnel, this will result in a PFE wedge condition due to which traffic gets impacted. As this is not a crash and restart scenario, this condition will persist until the system is rebooted to recover.

This issue affects Juniper Networks Junos OS on QFX10000:

20.3 version 20.3R1 and later versions;

20.4 versions prior to 20.4R3-S5;

21.1 versions prior to 21.1R3-S5;

21.2 versions prior to 21.2R3-S5;

21.3 versions prior to 21.3R3-S4;

21.4 versions prior to 21.4R3-S1;

22.1 versions prior to 22.1R3;

22.2 versions prior to 22.2R2;

22.3 versions prior to 22.3R1-S2, 22.3R2.

Remediation

Check the references section for vendor advisories and patches from juniper. Update junos to the latest patched version. If immediate patching is not possible, review the CVSS vector to understand the attack surface and apply compensating controls such as network segmentation or access restrictions.

Affected Products

References