CVE-2021-0202 - CVE House
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Status published High CVE-2021-0202

Junos OS: MX Series, EX9200 Series: Trio-based MPC memory leak when Integrated Routing and Bridging (IRB) interface is mapped to a VPLS instance or a Bridge-Domain

Vulnerability Description

On Juniper Networks MX Series and EX9200 Series platforms with Trio-based MPC (Modular Port Concentrator) where Integrated Routing and Bridging (IRB) interface is configured and it is mapped to a VPLS instance or a Bridge-Domain, certain network events at Customer Edge (CE) device may cause memory leak in the MPC which can cause an out of memory and MPC restarts. When this issue occurs, there will be temporary traffic interruption until the MPC is restored. An administrator can use the following CLI command to monitor the status of memory usage level of the MPC: user@device> show system resource-monitor fpc FPC Resource Usage Summary Free Heap Mem Watermark : 20 % Free NH Mem Watermark : 20 % Free Filter Mem Watermark : 20 % * - Watermark reached Slot # % Heap Free RTT Average RTT 1 87 PFE # % ENCAP mem Free % NH mem Free % FW mem Free 0 NA 88 99 1 NA 89 99 When the issue is occurring, the value of “% NH mem Free” will go down until the MPC restarts. This issue affects MX Series and EX9200 Series with Trio-based PFEs (Packet Forwarding Engines). Please refer to https://kb.juniper.net/KB25385 for the list of Trio-based PFEs. This issue affects Juniper Networks Junos OS on MX Series, EX9200 Series: 17.3R3-S8; 17.4R3-S2; 18.2R3-S4, 18.2R3-S5; 18.3R3-S2, 18.3R3-S3; 18.4 versions starting from 18.4R3-S1 and later versions prior to 18.4R3-S6; 19.2 versions starting from 19.2R2 and later versions prior to 19.2R3-S1; 19.4 versions starting from 19.4R2 and later versions prior to 19.4R2-S3, 19.4R3; 20.2 versions starting from 20.2R1 and later versions prior to 20.2R1-S3, 20.2R2. This issue does not affect Juniper Networks Junos OS: 18.1, 19.1, 19.3, 20.1.

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:
17.3R3-S8, 17.4R3-S2, 18.1, 19.1, 19.3, 20.1, 18.2R3-S4, 18.3R3-S2, 18.4R3-S1, 19.2R2, 19.4R2, 20.2R1

Timeline

Official Publish: January 15th, 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:U/C:N/I:N/A:H

Weaknesses (CWE)