CVE-2024-21600

published 2024-01-12

CVE-2024-21600: An Improper Neutralization of Equivalent Special Elements vulnerability in the Packet Forwarding Engine (PFE) of Juniper Networks Junos OS on PTX Series allows…

Priority P4 28 medium 6.5 CVSS 3.1

AV A AC L PR N UI N S U C N I N A H

An Improper Neutralization of Equivalent Special Elements vulnerability in the Packet Forwarding Engine (PFE) of Juniper Networks Junos OS on PTX Series allows a unauthenticated, adjacent attacker to cause a Denial of Service (DoS).

When MPLS packets are meant to be sent to a flexible tunnel interface (FTI) and if the FTI tunnel is down, these will hit the reject NH, due to which the packets get sent to the CPU and cause a host path wedge condition. This will cause the FPC to hang and requires a manual restart to recover.

Please note that this issue specifically affects PTX1000, PTX3000, PTX5000 with FPC3, PTX10002-60C, and PTX10008/16 with LC110x. Other PTX Series devices and Line Cards (LC) are not affected.

The following log message can be seen when the issue occurs:

Cmerror Op Set: Host Loopback: HOST LOOPBACK WEDGE DETECTED IN PATH ID (URI: /fpc//pfe//cm//Host_Loopback//HOST_LOOPBACK_MAKE_CMERROR_ID[])
This issue affects Juniper Networks Junos OS:

* All versions earlier than 20.4R3-S8;
* 21.1 versions earlier than 21.1R3-S4;
* 21.2 versions earlier than 21.2R3-S6;
* 21.3 versions earlier than 21.3R3-S3;
* 21.4 versions earlier than 21.4R3-S5;
* 22.1 versions earlier than 22.1R2-S2, 22.1R3;
* 22.2 versions earlier than 22.2R2-S1, 22.2R3.

Affected

15 ranges

Vendor	Product	Version range	Fixed in
juniper	junos	—	—
juniper	junos	—	—
juniper	junos	—	—
juniper	junos	—	—
juniper	junos	—	—
juniper	junos	—	—
juniper	junos	—	—
juniper	junos_os	—	—
juniper_networks	junos_os	< 20.4R3-S8	20.4R3-S8
juniper_networks	junos_os	>= 21.1 < 21.1R3-S4	21.1R3-S4
juniper_networks	junos_os	>= 21.2 < 21.2R3-S6	21.2R3-S6
juniper_networks	junos_os	>= 21.3 < 21.3R3-S3	21.3R3-S3
juniper_networks	junos_os	>= 21.4 < 21.4R3-S5	21.4R3-S5
juniper_networks	junos_os	>= 22.1 < 22.1R2-S2, 22.1R3	22.1R2-S2, 22.1R3
juniper_networks	junos_os	>= 22.2 < 22.2R2-S1, 22.2R3	22.2R2-S1, 22.2R3

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CWE-76