Product Affected

This issue affects all versions of Junos OS. Affected platforms: MX Series.
High

CVSS: v3.1: 7.5 (CVSS:3.1/AV:N/AC:L/PR:N/UI:N/S:U/C:N/I:N/A:H)
CVSS: v4.0: 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/AU:Y/RE:M)

Problem

An Improper Check for Unusual or Exceptional Conditions vulnerability in the Packet Forwarding Engine (pfe) of Juniper Networks Junos OS on MX Series allows an unauthenticated, network-based attacker to cause a Denial-of-Service (DoS).

 

When processing a high rate of specific GRE traffic destined to the device, the respective PFE will hang causing traffic forwarding to stop.

 

When this issue occurs the following logs can be observed:

<fpc #> MQSS(0): LI-3: Received a parcel with more than 512B accompanying data
CHASSISD_FPC_ASIC_ERROR: ASIC Error detected <...>

 

This issue affects Junos OS:

  • all versions before 21.2R3-S9,
  • 21.4 versions before 21.4R3-S8,
  • 22.2 versions before 22.2R3-S4,
  • 22.4 versions before 22.4R3-S5,
  • 23.2 versions before 23.2R2-S2,
  • 23.4 versions before 23.4R2.

 

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: 21.2R3-S9, 21.4R3-S8, 22.2R3-S4, 22.4R3-S5, 23.2R2-S2, 23.4R2, 24.2R1, and all subsequent releases.

 

This issue is being tracked as 1784246 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

2025-04-09: Initial Publication

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