Medium severity · published Jul 10, 2024
CVE-2024-39557
Junos OS Evolved: MAC table changes cause a memory leak
6.5
CVSS
0.2%
EPSS
No
On KEV
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.
CVSS vector
CVSS:3.1/AV:A/AC:L/PR:N/UI:N/S:U/C:N/I:N/A:H
Attack vector
Adjacent
Complexity
Low
Privileges
None
User interaction
None
Confidentiality
None
Integrity
None
Availability
High
Scope
Unchanged
Exploitation
Is it being used?
Exploit prediction (EPSS)0.2% · higher than 16% of CVEs
Exploited in the wildNo evidence yet
CISA KEVNot listed
Ransomware campaign useNot known
Affected products
Which versions
JO
Junos OS Evolved · Juniper Networks
before 21.4R3-S8-EVO; 22.2-EVO before 22.2R3-S4-EVO; 22.3-EVO before 22.3R3-S3-EVO; 22.4-EVO before 22.4R3-EVO; 23.2-EVO before 23.2R2-EVO · source: vendor, NVD
Affected product
JO
Junos OS Evolved
Juniper Networks
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