SOC status:Duty analyst on shift

UK Cyber Defence
VulnerabilityModified

CVE-2018-0021

Hence, Juniper devices configured with short MacSec keys are at risk to an increased likelihood that an attacker will discover the secret passphrases configured for these keys through dictionary-based and brute-force-based attacks using spoofed packets.

HIGH 8.8EPSS 0.60%

Does this matter?

High impact if exploited, but EPSS currently rates exploitation as unlikely (0.60%). Schedule it in the normal patch cycle and watch for a rise in EPSS or a public exploit.

Description

If all 64 digits of the connectivity association name (CKN) key or all 32 digits of the connectivity association key (CAK) key are not configured, all remaining digits will be auto-configured to 0. Hence, Juniper devices configured with short MacSec keys are at risk to an increased likelihood that an attacker will discover the secret passphrases configured for these keys through dictionary-based and brute-force-based attacks using spoofed packets. Affected releases are Juniper Networks Junos OS: 14.1 versions prior to 14.1R10, 14.1R9; 14.1X53 versions prior to 14.1X53-D47; 15.1 versions prior to 15.1R4-S9, 15.1R6-S6, 15.1R7; 15.1X49 versions prior to 15.1X49-D100; 15.1X53 versions prior to 15.1X53-D59; 16.1 versions prior to 16.1R3-S8, 16.1R4-S8, 16.1R5; 16.2 versions prior to 16.2R1-S6, 16.2R2; 17.1 versions prior to 17.1R2.

CVSS 3.0
8.8 HIGHCVSS:3.0/AV:A/AC:L/PR:N/UI:N/S:U/C:H/I:H/A:H
EPSS
0.60% probability · 48th percentile
Public exploits
None in Exploit-DB
CISA KEV
Not listed
Affected
juniper/junos
Source
sirt@juniper.net
EPSS trend
0%3%5%27 October 2026: 0.60%27 October 202627 October 2026

EPSS 0.6% since 27 October 2026; no change recorded yet. Points are recorded when the score first appears and whenever it moves by a percentage point or more.

References

Source: NVD record, EPSS from FIRST.org, KEV from CISA, exploits from Exploit-DB. Refreshed daily. Download this record as JSON.