CVE-2021-0234 - CVE House
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Status published Medium CVE-2021-0234

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

Vulnerability 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;

Impact Analysis

Refer to official advisory for detailed impact metrics.

Remediation

Ensure systems are updated to the latest vendor-supplied patch levels.

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Credits & Attribution

No credits recorded in the NVD database.

Affected Vendor

Juniper Networks

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Affected Software

Junos OS
Vulnerable Versions:
17.3, 17.4, 18.1, 18.2, 18.3, 18.4, 19.1, 19.2, 19.3, 19.4

Timeline

Official Publish: April 22nd, 2021
Last Modified: September 17th, 2024
Added to House: July 21st, 2026

CVSS Vectors

V3: CVSS:3.1/AV:N/AC:L/PR:N/UI:N/S:C/C:N/I:N/A:L

Weaknesses (CWE)

MITRE ATT&CK TTPs

No associated TTPs found for this vulnerability.