CVE-2023-36833: Junos OS Evolved: PTX10001-36MR, and PTX10004, PTX10008, PTX10016 with LC1201/1202: The aftman-bt process will crash in a MoFRR scenario after multiple link flaps
A Use After Free vulnerability in the packet forwarding engine (PFE) of Juniper Networks Junos OS Evolved on PTX10001-36MR, and PTX10004, PTX10008, PTX10016 with LC1201/1202 allows an adjacent, unauthenticated attacker to cause a Denial of Service (DoS).
The process 'aftman-bt' will crash after multiple flaps on a multicast-only fast reroute (MoFRR) enabled interface. This will cause the respective FPC to stop forwarding traffic and it needs to be rebooted to restore the service.
An indication that the system experienced this issue is the following log message:
<date> <hostname> evo-aftmand-bt[<pid>]: [Error] jexprfdb: sanity check failed, ... , appname L3 Mcast Routes
This issue affects Juniper Networks Junos OS Evolved on PTX10001-36MR, PTX10004, PTX10008, PTX10016 with LC1201/1202: 21.2 version 21.2R1-EVO and later versions; 21.3 version 21.3R1-EVO and later versions; 21.4 versions prior to 21.4R3-S3-EVO; 22.1 version 22.1R1-EVO and later versions; 22.2 versions prior to 22.2R3-S2-EVO; 22.3 versions prior to 22.3R3-EVO; 22.4 versions prior to 22.4R1-S2-EVO, 22.4R2-EVO.
Affected Software
Remediation
Recommended actions to resolve this vulnerability, in priority order.
- Upgrade
Upgrade
Juniper Networks Junos OS Evolved (L3 Mcast Routes / packet forwarding engine)to a version that resolves this vulnerability.Fixed in 21.4R3-S3-EVO - Upgrade
Upgrade
Juniper Networks Junos OS Evolved (L3 Mcast Routes / packet forwarding engine)to a version that resolves this vulnerability.Fixed in 22.2R3-S2-EVO - Upgrade
Upgrade
Juniper Networks Junos OS Evolved (L3 Mcast Routes / packet forwarding engine)to a version that resolves this vulnerability.Fixed in 22.3R3-EVO - Upgrade
Upgrade
Juniper Networks Junos OS Evolved (L3 Mcast Routes / packet forwarding engine)to a version that resolves this vulnerability.Fixed in 22.4R1-S2-EVO - Upgrade
Upgrade
Juniper Networks Junos OS Evolved (L3 Mcast Routes / packet forwarding engine)to a version that resolves this vulnerability.Fixed in 22.4R2-EVO - Upgrade
Upgrade
Juniper Networks Junos OS Evolved (L3 Mcast Routes / packet forwarding engine)to a version that resolves this vulnerability.Fixed in 23.1R1-EVO - Operational
If the FPC stops forwarding traffic due to an 'aftman-bt' crash after multiple flaps in a MoFRR scenario on a multicast-only fast reroute (MoFRR) enabled interface, reboot the FPC to restore service, as the text states reboot is needed to restore forwarding.
Event History
Frequently Asked Questions
What is the severity of CVE-2023-36833?
CVE-2023-36833 has been classified as a Denial of Service vulnerability with a high severity due to its potential impact on affected systems.
How do I fix CVE-2023-36833?
To mitigate CVE-2023-36833, ensure you update your Junos OS Evolved to a version that is not affected by this vulnerability as per the vendor's guidance.
Which versions are affected by CVE-2023-36833?
CVE-2023-36833 affects Junos OS Evolved versions 21.2, 21.3, 21.4, and several revisions within these versions.
What kind of attack can exploit CVE-2023-36833?
CVE-2023-36833 can be exploited by an adjacent, unauthenticated attacker to cause a Denial of Service condition.
What products are impacted by CVE-2023-36833?
The vulnerable products include Juniper Networks PTX10001-36MR, PTX10004, PTX10008, and PTX10016 running specific versions of Junos OS Evolved.