CVE-2023-36850: Junos OS: MX Series: An MPC will crash upon receipt of a malformed CFM packet.
An Improper Validation of Specified Index, Position, or Offset in Input vulnerability in the Connectivity Fault Management(CFM) module of Juniper Networks Junos OS on MX Series(except MPC10, MPC11 and LC9600) allows an adjacent attacker on the local broadcast domain to cause a Denial of Service(DoS).
Upon receiving a malformed CFM packet, the MPC crashes. Continued receipt of these packets causes a sustained denial of service. This issue can only be triggered when CFM hasn't been configured.
This issue affects: Juniper Networks Junos OS All versions prior to 19.1R3-S10 on MX Series; 19.2 versions prior to 19.2R3-S7 on MX Series; 19.3 versions prior to 19.3R3-S8 on MX Series; 19.4 versions prior to 19.4R3-S12 on MX Series; 20.1 version 20.1R1 and later versions on MX Series; 20.2 versions prior to 20.2R3-S7 on MX Series; 20.3 version 20.3R1 and later versions on MX Series; 20.4 versions prior to 20.4R3-S7 on MX Series; 21.1 versions prior to 21.1R3-S5 on MX Series; 21.2 versions prior to 21.2R3-S4 on MX Series; 21.3 versions prior to 21.3R3-S4 on MX Series; 21.4 versions prior to 21.4R3-S3 on MX Series; 22.1 versions prior to 22.1R3-S2 on MX Series; 22.2 versions prior to 22.2R3 on MX Series; 22.3 versions prior to 22.3R2, 22.3R3 on MX Series; 22.4 versions prior to 22.4R2 on MX Series.
Affected Software
Remediation
Recommended actions to resolve this vulnerability, in priority order.
- Upgrade
Upgrade
Junos OS (MX Series)to a version that resolves this vulnerability.Fixed in 19.1R3-S10 - Upgrade
Upgrade
Junos OS (MX Series)to a version that resolves this vulnerability.Fixed in 19.2R3-S7 - Upgrade
Upgrade
Junos OS (MX Series)to a version that resolves this vulnerability.Fixed in 19.4R3-S12 - Upgrade
Upgrade
Junos OS (MX Series)to a version that resolves this vulnerability.Fixed in 20.2R3-S7 - Upgrade
Upgrade
Junos OS (MX Series)to a version that resolves this vulnerability.Fixed in 20.4R3-S7 - Upgrade
Upgrade
Junos OS (MX Series)to a version that resolves this vulnerability.Fixed in 21.1R3-S5 - Upgrade
Upgrade
Junos OS (MX Series)to a version that resolves this vulnerability.Fixed in 21.2R3-S4 - Upgrade
Upgrade
Junos OS (MX Series)to a version that resolves this vulnerability.Fixed in 21.3R3-S4 - Upgrade
Upgrade
Junos OS (MX Series)to a version that resolves this vulnerability.Fixed in 21.4R3-S3 - Upgrade
Upgrade
Junos OS (MX Series)to a version that resolves this vulnerability.Fixed in 22.1R3-S2 - Upgrade
Upgrade
Junos OS (MX Series)to a version that resolves this vulnerability.Fixed in 22.2R3 - Upgrade
Upgrade
Junos OS (MX Series)to a version that resolves this vulnerability.Fixed in 22.3R2 - Upgrade
Upgrade
Junos OS (MX Series)to a version that resolves this vulnerability.Fixed in 22.3R3 - Upgrade
Upgrade
Junos OS (MX Series)to a version that resolves this vulnerability.Fixed in 22.4R2 - Upgrade
Upgrade
Junos OS (MX Series)to a version that resolves this vulnerability.Fixed in 23.1R1 - Compensating control
Configure CFM on the MX Series so the issue cannot be triggered (the vulnerability can only be triggered when CFM hasn't been configured).
Event History
Frequently Asked Questions
What is the severity of CVE-2023-36850?
The severity of CVE-2023-36850 is considered high due to the potential for Denial of Service (DoS) attacks.
How do I fix CVE-2023-36850?
To fix CVE-2023-36850, upgrade to the latest version of Junos OS that has addressed this vulnerability.
Who is affected by CVE-2023-36850?
CVE-2023-36850 affects Juniper Networks Junos OS on MX Series devices, except for MPC10, MPC11, and LC9600.
What type of vulnerability is CVE-2023-36850?
CVE-2023-36850 is classified as an Improper Validation of Specified Index, Position, or Offset in Input vulnerability.
Can CVE-2023-36850 be exploited remotely?
Yes, CVE-2023-36850 can be exploited by an adjacent attacker on the local broadcast domain.