CVE-2021-0234

Junos OS: QFX5100-96S: DDoS protection does not work as expected.

Description

Due to an improper Initialization vulnerability on Juniper Networks Junos OS QFX5100-96S devices with QFX 5e Series image installed, ddos-protection configuration changes will not take effect beyond the default DDoS (Distributed Denial of Service) settings when configured from the CLI. The DDoS protection (jddosd) daemon allows the device to continue to function while protecting the packet forwarding engine (PFE) during the DDoS attack. When this issue occurs, the default DDoS settings within the PFE apply, as CPU bound packets will be throttled and dropped in the PFE when the limits are exceeded. To check if the device has this issue, the administrator can execute the following command to monitor the status of DDoS protection: user@device> show ddos-protection protocols error: the ddos-protection subsystem is not running This issue affects only QFX5100-96S devices. No other products or platforms are affected by this issue. This issue affects: Juniper Networks Junos OS on QFX5100-96S: 17.3 versions prior to 17.3R3-S10; 17.4 versions prior to 17.4R3-S4; 18.1 versions prior to 18.1R3-S10; 18.2 versions prior to 18.2R3-S3; 18.3 versions prior to 18.3R3-S2; 18.4 versions prior to 18.4R2-S4, 18.4R3-S1; 19.1 versions prior to 19.1R3, 19.1R3-S4; 19.2 versions prior to 19.2R2; 19.3 versions prior to 19.3R3; 19.4 versions prior to 19.4R2;

Remediation

Solution:

  • The following software releases have been updated to resolve this specific issue: 17.3R3-S10, 17.4R3-S4, 18.1R3-S10, 18.2R3-S3, 18.3R3-S2, 18.4R2-S4, 18.4R3-S1, 19.1R3, 19.1R3-S4, 19.2R2, 19.3R3, 19.4R2, 20.1R1, and all subsequent releases.

Workaround:

  • The following command can be used to enable ddos-protection manually: root@device% /usr/sbin/jddosd -N &

Category

5.8
CVSS
Severity: Medium
CVSS 3.1 •
CVSS 2.0 •
EPSS 0.27%
Vendor Advisory juniper.net
Affected: Juniper Networks Junos OS
Published at:
Updated at:

References

Link Tags
https://kb.juniper.net/JSA11129 vendor advisory

Frequently Asked Questions

What is the severity of CVE-2021-0234?
CVE-2021-0234 has been scored as a medium severity vulnerability.
How to fix CVE-2021-0234?
To fix CVE-2021-0234: The following software releases have been updated to resolve this specific issue: 17.3R3-S10, 17.4R3-S4, 18.1R3-S10, 18.2R3-S3, 18.3R3-S2, 18.4R2-S4, 18.4R3-S1, 19.1R3, 19.1R3-S4, 19.2R2, 19.3R3, 19.4R2, 20.1R1, and all subsequent releases.
Is CVE-2021-0234 being actively exploited in the wild?
As for now, there are no information to confirm that CVE-2021-0234 is being actively exploited. According to its EPSS score, there is a ~0% probability that this vulnerability will be exploited by malicious actors in the next 30 days.
What software or system is affected by CVE-2021-0234?
CVE-2021-0234 affects Juniper Networks Junos OS.
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