Resource exhaustion in Juniper Ex2300

CVE-2020-1668

On Juniper Networks EX2300 Series, receipt of a stream of specific multicast packets by the layer2 interface can cause high CPU load, which could lead to traffic interruption. This issue occurs when multicast packets are received by the layer 2 interface. To check if the device has high CPU load due to this issue, the administrator can issue the following command: user@host> show chassis routing-engine Routing Engine status: ... Idle 2 percent the "Idle" value shows as low (2 % in the example above), and also the following command: user@host> show system processes summary ... PID USERNAME PRI NICE SIZE RES STATE TIME WCPU COMMAND 11639 root 52 0 283M 11296K select 12:15 44.97% eventd 11803 root 81 0 719M 239M RUN 251:12 31.98% fxpc{fxpc} the eventd and the fxpc processes might use higher WCPU percentage (respectively 44.97% and 31.98% in the above example). This issue affects Juniper Networks Junos OS on EX2300 Series: 18.1 versions prior to 18.1R3-S11; 18.2 versions prior to 18.2R3-S5; 18.3 versions prior to 18.3R2-S4, 18.3R3-S3; 18.4 versions prior to 18.4R2-S5, 18.4R3-S4; 19.1 versions prior to 19.1R3-S2; 19.2 versions prior to 19.2R1-S5, 19.2R3; 19.3 versions prior to 19.3R2-S4, 19.3R3; 19.4 versions prior to 19.4R1-S3, 19.4R2-S1, 19.4R3; 20.1 versions prior to 20.1R1-S2, 20.1R2.

Vulnerability class: DoS (Denial of Service)

EPSS: 0.005 (40.5th percentile) — read the EPSS interpretation.

CVSS v3 metric

CVSS v3 base score 6.5 (Medium). Vector: CVSS:3.1/AV:A/AC:L/PR:N/UI:N/S:U/C:N/I:N/A:H.

Affected products

Weakness classification (CWE)

References

Frequently asked questions

What is CVE-2020-1668?
CVE-2020-1668 is a medium-severity vulnerability in Juniper Ex2300, classified under Uncontrolled Resource Consumption. CVSS score: 6.5/10. Published 2020-10-16.
How severe is CVE-2020-1668?
Medium severity. CVSS v3 base score is 6.5 out of 10.