Product Affected

This issue affects Junos OS , 19.2, 19.3, 19.4, 20.1, 20.2, 20.3, 20.4, 21.1, 21.2, 21.3, 21.4, 22.1, 22.2, 22.3, 22.4. Affected platforms: MX Series.
Medium
6.5 (CVSS:3.1/AV:A/AC:L/PR:N/UI:N/S:U/C:N/I:N/A:H)

Problem

An Improper Handling of Undefined Values vulnerability in the periodic packet management daemon (PPMD) of Juniper Networks Junos OS on MX Series(except MPC10, MPC11 and LC9600) allows an unauthenticated adjacent attacker to cause a Denial of Service (DoS).
 

When a malformed CFM packet is received, it leads to an FPC crash. Continued receipt of these packets causes a sustained denial of service. This vulnerability occurs only when CFM has been configured on the interface.
 

This issue affects:

Juniper Networks Junos OS

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-S8 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-S5 on MX Series;

21.3 versions prior to 21.3R3-S4 on MX Series;

21.4 versions prior to 21.4R3-S4 on MX Series;

22.1 versions prior to 22.1R3-S3 on MX Series;

22.2 versions prior to 22.2R3-S1 on MX Series;

22.3 versions prior to 22.3R3 on MX Series;

22.4 versions prior to 22.4R1-S2, 22.4R2 on MX Series.

CFM can be configured using the following command:

[protocols oam ethernet connectivity-fault-management maintenance-domain <md-name> level <number>]
 

Juniper SIRT is not aware of any malicious exploitation of this vulnerability.

This issue was seen during production usage.

This issue has been assigned CVE-2023-36848.

Solution

The following software releases have been updated to resolve this specific issue: 19.1R3-S10, 19.2R3-S7, 19.3R3-S8, 19.4R3-S12, 20.2R3-S8, 20.4R3-S7, 21.1R3-S5, 21.2R3-S5, 21.3R3-S4, 21.4R3-S4, 22.1R3-S3, 22.2R3-S1, 22.3R3, 22.4R1-S2, 22.4R2, 23.1R1, and all subsequent releases.

This issue is being tracked as 1714149

Note: Juniper SIRT's policy is not to evaluate releases which are beyond End of Engineering (EOE) or End of Life (EOL).

Workaround

There are no known workarounds for this issue.

Severity Assessment

Information for how Juniper Networks uses CVSS can be found at KB 16446 [juniper.net] "Common Vulnerability Scoring System (CVSS) and Juniper's Security Advisories.

Modification History

2023-07-12: Initial Publication

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