CVE-2026-102033: Junos OS and Junos OS Evolved: An attacker causes denial of service when MC-LAG MAC synchronization is enabled

Medium severity · published Oct 14, 2026

CVE-2026-102033

Junos OS and Junos OS Evolved: An attacker causes denial of service when MC-LAG MAC synchronization is enabled

6.5

CVSS

0.3%

EPSS

On KEV

Description

An Improper Validation of Specified Quantity in Input vulnerability in l2ald of Juniper Networks Junos OS and Junos OS Evolved allows an adjacent attacker to cause a denial of service via an ICCP MC-LAG message.

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)0.3% · higher than 19% of CVEs

Exploited in the wildNo evidence yet

CISA KEVNot listed

Ransomware campaign useNot known

Affected products

Which versions

Junos OS · Juniper

before 23.2R2-S7.7; 23.4 before 23.4R2-S8.13; 24.2 before 24.2R2-S5.5; 24.4 before 24.4R2-S5; 25.2 before 25.2R2-S2; 25.4 before 25.4R1-S3; +1 more · source: vendor

Junos OS Evolved · Juniper Networks

before 23.2R2-S7.7-EVO; 23.4 before 23.4R2-S8.11-EVO; 24.2 before 24.2R2-S5.6-EVO; 24.4 before 24.4R2-S5-EVO; 25.2 before 25.2R2-S2-EVO; 25.4 before 25.4R1-S3-EVO; +4 more · source: vendor

Affected product

Junos OS

Juniper

All Junos OS CVEs

References

NVD

https://nvd.nist.gov/vuln/detail/CVE-2026-102033

CVE.org

https://www.cve.org/CVERecord?id=CVE-2026-102033

vendor-advisory

https://supportportal.juniper.net/JSA112187