CVE-2023-36850

Junos OS: MX Series: An MPC will crash upon receipt of a malformed CFM packet.

Description

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.

Remediation

Solution:

  • The following software releases have been updated to resolve this specific issue: Junos OS 19.1R3-S10, 19.2R3-S7, 19.4R3-S12, 20.2R3-S7, 20.4R3-S7, 21.1R3-S5, 21.2R3-S4, 21.3R3-S4, 21.4R3-S3, 22.1R3-S2, 22.2R3, 22.3R2, 22.3R3, 22.4R2, 23.1R1, and all subsequent releases.

Workaround:

  • There are no known workarounds for this issue.

Category

6.5
CVSS
Severity: Medium
CVSS 3.1 •
EPSS 0.06%
Vendor Advisory juniper.net
Affected: Juniper Networks Junos OS
Published at:
Updated at:

References

Frequently Asked Questions

What is the severity of CVE-2023-36850?
CVE-2023-36850 has been scored as a medium severity vulnerability.
How to fix CVE-2023-36850?
To fix CVE-2023-36850: The following software releases have been updated to resolve this specific issue: Junos OS 19.1R3-S10, 19.2R3-S7, 19.4R3-S12, 20.2R3-S7, 20.4R3-S7, 21.1R3-S5, 21.2R3-S4, 21.3R3-S4, 21.4R3-S3, 22.1R3-S2, 22.2R3, 22.3R2, 22.3R3, 22.4R2, 23.1R1, and all subsequent releases.
Is CVE-2023-36850 being actively exploited in the wild?
As for now, there are no information to confirm that CVE-2023-36850 is being actively exploited. According to its EPSS score, there is a ~0% probability that this vulnerability will be exploited by malicious actors in the next 30 days.
What software or system is affected by CVE-2023-36850?
CVE-2023-36850 affects Juniper Networks Junos OS.
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