CVE-2021-31367

MediumCVSS 6.5/10Last modified Jun 17, 2026

Description

A Missing Release of Memory after Effective Lifetime vulnerability in the Packet Forwarding Engine (PFE) of Juniper Networks Junos OS on PTX Series allows an adjacent attacker to cause a Denial of Service (DoS) by sending genuine BGP flowspec packets which cause an FPC heap memory leak. Once having run out of memory the FPC will crash and restart along with a core dump. Continued receipted of these packets will create a sustained Denial of Service (DoS) condition. This issue affects: Juniper Networks Junos OS All versions prior to 18.4R3-S9; 19.1 versions prior to 19.1R3-S7; 19.2 versions prior to 19.2R1-S7, 19.2R3-S3; 19.3 versions prior to 19.3R2-S6, 19.3R3-S3; 19.4 versions prior to 19.4R1-S4, 19.4R3-S6; 20.1 versions prior to 20.1R2-S2, 20.1R3; 20.2 versions prior to 20.2R3-S1; 20.3 versions prior to 20.3R3; 20.4 versions prior to 20.4R3; 21.1 versions prior to 21.1R2. Juniper Networks Junos Evolved is not affected.

Metrics

CVSS 3.1 6.5/10CVSS:3.1/AV:A/AC:L/PR:N/UI:N/S:U/C:N/I:N/A:H

Weakness enumeration

Affected software

No affected versions have been published.

Timeline

Published
Oct 19, 2021
Last modified
Jun 17, 2026
NVD status
Modified

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CVE-2021-31367: Medium severity, CVSS 6.5 | Vulnix