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
References
NVD
https://nvd.nist.gov/vuln/detail/CVE-2024-39557
CVE.org
https://www.cve.org/CVERecord?id=CVE-2024-39557
Vendor Advisory
https://supportportal.juniper.net/JSA83017
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