Product Affected

This issue affects all versions of Junos OS Evolved on ACX 7000 Series.
High
CVSS 3.1: 7.5 (CVSS:3.1/AV:N/AC:L/PR:N/UI:N/S:U/C:N/I:N/A:H)
CVSS 4.0: 8.7 (CVSS:4.0/AV:N/AC:L/AT:N/PR:N/UI:N/VC:N/VI:N/VA:H/SC:N/SI:N/SA:L)

Problem

An Improper Handling of Values vulnerability in the Packet Forwarding Engine (PFE) of Juniper Networks Junos OS Evolved on ACX 7000 Series allows a network-based, unauthenticated attacker to cause a Denial-of-Service (DoS).
 

If a value is configured for DDoS bandwidth or burst parameters for any protocol in a queue, all protocols which share the same queue will have their bandwidth or burst value changed to the new value. If, for example, OSPF was configured with a certain bandwidth value, ISIS would also be limited to this value. So inadvertently either the control plane is open for a high level of specific traffic which was supposed to be limited to a lower value, or the limit for a certain protocol is so low that chances to succeed with a volumetric DoS attack are significantly increased. 

 

This issue affects Junos OS Evolved on ACX 7000 Series:

  • All versions before 21.4R3-S7-EVO,
  • 22.1 versions before 22.1R3-S6-EVO, 
  • 22.2 versions before 22.2R3-S3-EVO,
  • 22.3 versions before 22.3R3-S3-EVO, 
  • 22.4 versions before 22.4R3-S2-EVO,
  • 23.2 versions before 23.2R2-EVO,
  • 23.4 versions before 23.4R1-S1-EVO, 23.4R2-EVO.

 

To be exposed to this issue noticeably low or high values for a specific protocol have to be configured, which then also effect other protocols:

[ system ddos-protection protocols <protocol> aggregate bandwidth <bandwidth> ]
[ system ddos-protection protocols <protocol> aggregate burst <burst> ]

 

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

This issue was seen during production usage.

Solution

The following software releases have been updated to resolve this specific issue: 21.4R3-S7-EVO, 22.1R3-S6-EVO, 22.2R3-S3-EVO, 22.3R3-S3-EVO, 22.4R3-S2-EVO, 23.2R2-EVO, 23.4R1-S1-EVO, 23.4R2-EVO, 24.2R1-EVO, and all subsequent releases.
 

This issue is being tracked as 1784343 which is visible on the Customer Support website.
 

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

2024-07-10: Initial Publication
2024-09-13: Minor formatting change to CVSS field

Related Information