What is the CVSS score of CVE-2024-21600?

CVE-2024-21600 has a CVSS 3.1 base score of 6.5 (Medium). CVSS vector: CVSS:3.1/AV:A/AC:L/PR:N/UI:N/S:U/C:N/I:N/A:H. EPSS exploitation probability: 0.0%.

Which versions of Junos are affected by CVE-2024-21600?

CVE-2024-21600 presents notable security risk rated CVSS 6.5. Exploitation could compromise the security of affected deployments.

How to fix or mitigate CVE-2024-21600?

Within 30 days: Identify affected systems and apply vendor patches as part of regular patch cycle. Monitor vendor channels for patch availability.

Junos CVE-2024-21600

MEDIUM

Improper Neutralization of Equivalent Special Elements (CWE-76)

2024-01-12 sirt@juniper.net

Denial Of Service Juniper Junos

6.5

CVSS 3.1 · NVD

Severity by source

NVD PRIMARY

6.5 MEDIUM

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

Primary rating from NVD · only source for this CVE.

CVSS VectorNVD

CVSS:3.1/AV:A/AC:L/PR:N/UI:N/S:U/C:N/I:N/A:H

Attack Vector

Adjacent

Attack Complexity

Low

Privileges Required

None

User Interaction

None

Scope

Unchanged

Confidentiality

None

Integrity

None

Availability

High

Lifecycle Timeline

Analysis Generated

Mar 28, 2026 - 19:34 vuln.today

CVE Published

Jan 12, 2024 - 01:15 nvd

MEDIUM 6.5

DescriptionCVE.org

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 <id> (URI: /fpc/<fpc>/pfe/<pfe>/cm/<cm>/Host_Loopback/<cm>/HOST_LOOPBACK_MAKE_CMERROR_ID[<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.

AnalysisAI

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. Rated medium severity (CVSS 6.5), this vulnerability is no authentication required, low attack complexity. No vendor patch available.

Technical ContextAI

This vulnerability is classified under CWE-76. 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 <id> (URI: /fpc/<fpc>/pfe/<pfe>/cm/<cm>/Host_Loopback/<cm>/HOST_LOOPBACK_MAKE_CMERROR_ID[<id>])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 products include: Juniper Junos.

RemediationAI

No vendor patch is available at time of analysis. Monitor vendor advisories for updates. Apply vendor patches when available. Implement network segmentation and monitoring as interim mitigations.