CVE-2023-36835: Junos OS: QFX10000 Series: All traffic will be dropped after a specific valid IP packet has been received which needs to be routed over a VXLAN tunnel
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.
Affected Software
Remediation
Recommended actions to resolve this vulnerability, in priority order.
- Upgrade
Upgrade
Juniper Networks Junos OS (QFX10000 Series Packet Forwarding Engine - PFE)to a version that resolves this vulnerability.Fixed in 20.4R3-S5 - Upgrade
Upgrade
Juniper Networks Junos OS (QFX10000 Series Packet Forwarding Engine - PFE)to a version that resolves this vulnerability.Fixed in 21.1R3-S5 - Upgrade
Upgrade
Juniper Networks Junos OS (QFX10000 Series Packet Forwarding Engine - PFE)to a version that resolves this vulnerability.Fixed in 21.2R3-S5 - Upgrade
Upgrade
Juniper Networks Junos OS (QFX10000 Series Packet Forwarding Engine - PFE)to a version that resolves this vulnerability.Fixed in 21.3R3-S4 - Upgrade
Upgrade
Juniper Networks Junos OS (QFX10000 Series Packet Forwarding Engine - PFE)to a version that resolves this vulnerability.Fixed in 21.4R3-S1 - Upgrade
Upgrade
Juniper Networks Junos OS (QFX10000 Series Packet Forwarding Engine - PFE)to a version that resolves this vulnerability.Fixed in 22.1R3 - Upgrade
Upgrade
Juniper Networks Junos OS (QFX10000 Series Packet Forwarding Engine - PFE)to a version that resolves this vulnerability.Fixed in 22.2R2 - Upgrade
Upgrade
Juniper Networks Junos OS (QFX10000 Series Packet Forwarding Engine - PFE)to a version that resolves this vulnerability.Fixed in 22.3R1-S2 - Upgrade
Upgrade
Juniper Networks Junos OS (QFX10000 Series Packet Forwarding Engine - PFE)to a version that resolves this vulnerability.Fixed in 22.3R2 - Upgrade
Upgrade
Juniper Networks Junos OS (QFX10000 Series Packet Forwarding Engine - PFE)to a version that resolves this vulnerability.Fixed in 22.4R1 - Operational
If the PFE wedge/DoS condition occurs (traffic gets impacted after a specific valid IP packet that needs VXLAN-tunnel routing), recover by rebooting the system, since the condition persists until reboot.
Event History
Frequently Asked Questions
What is the severity of CVE-2023-36835?
CVE-2023-36835 has been classified as having a high severity level due to its potential to enable a Denial of Service attack.
How do I fix CVE-2023-36835?
To mitigate CVE-2023-36835, it is recommended to upgrade to the patched versions of Junos OS specified in the official advisory.
Who is affected by CVE-2023-36835?
CVE-2023-36835 affects Juniper Networks Junos OS on various QFX10000 Series switches.
What kind of attack does CVE-2023-36835 allow?
CVE-2023-36835 allows a network-based attacker to exploit the vulnerability to cause a Denial of Service (DoS) condition.
Is there a workaround for CVE-2023-36835?
There are currently no known workarounds for CVE-2023-36835, making an upgrade to a secure version the only effective solution.