CVE-2024-39557

Junos OS Evolved: MAC table changes cause a memory leak

Description

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.

Remediation

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.

Workaround:

  • There are no known workarounds for this issue.

Category

7.1
CVSS
Severity: High
CVSS 4.0 •
CVSS 3.1 •
EPSS 0.07%
Vendor Advisory juniper.net
Affected: Juniper Networks Junos OS Evolved
Published at:
Updated at:

References

Frequently Asked Questions

What is the severity of CVE-2024-39557?
CVE-2024-39557 has been scored as a high severity vulnerability.
How to fix CVE-2024-39557?
To fix CVE-2024-39557: 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.
Is CVE-2024-39557 being actively exploited in the wild?
As for now, there are no information to confirm that CVE-2024-39557 is being actively exploited. According to its EPSS score, there is a ~0% probability that this vulnerability will be exploited by malicious actors in the next 30 days.
What software or system is affected by CVE-2024-39557?
CVE-2024-39557 affects Juniper Networks Junos OS Evolved.
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