Product Affected

This issue affects Junos OS Evolved 21.2-EVO, 21.4-EVO, 22.2-EVO, 22.3-EVO, 22.4-EVO, 23.2-EVO.
Medium
CVSS 3.1: 6.5 (CVSS:3.1/AV:A/AC:L/PR:N/UI:N/S:U/C:N/I:N/A:H)
CVSS 4.0: 7.1 (CVSS:4.0/AV:A/AC:L/AT:N/PR:N/UI:N/VC:N/VI:N/VA:H/SC:N/SI:N/SA:L/R:A)

Problem

An Uncontrolled Resource Consumption vulnerability in the Layer 2 Address Learning Daemon (l2ald) of Juniper Networks Junos OS Evolved allows an unauthenticated, adjacent attacker to cause a memory leak, eventually exhausting all system memory, leading to a system crash and Denial of Service (DoS).

Certain MAC table updates cause a small amount of memory to leak.  Once memory utilization reaches its limit, the issue will result in a system crash and restart.

To identify the issue, execute the CLI command:

user@device> show platform application-info allocations app l2ald-agent
EVL Object Allocation Statistics:

Node   Application     Context Name                               Live   Allocs   Fails     Guids
re0   l2ald-agent               net::juniper::rtnh::L2Rtinfo       1069096 1069302   0         1069302
re0   l2ald-agent               net::juniper::rtnh::NHOpaqueTlv     114     195       0         195

 

This issue affects Junos OS Evolved:

  • All versions before 21.4R3-S8-EVO,
  • from 22.2-EVO before 22.2R3-S4-EVO,
  • from 22.3-EVO before 22.3R3-S3-EVO,
  • from 22.4-EVO before 22.4R3-EVO,
  • from 23.2-EVO before 23.2R2-EVO.
 

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-S8-EVO, 22.2R3-S4-EVO, 22.3R3-S3-EVO, 22.4R3-EVO, 23.2R2-EVO, 23.4R1-EVO, and all subsequent releases.


This issue is being tracked as 1756208 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

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