CVE-2021-0239

MediumCVSS 6.5/10Last modified Jun 17, 2026

Description

In Juniper Networks Junos OS Evolved, receipt of a stream of specific genuine Layer 2 frames may cause the Advanced Forwarding Toolkit (AFT) manager process (Evo-aftmand), responsible for handling Route, Class-of-Service (CoS), Firewall operations within the packet forwarding engine (PFE) to crash and restart, leading to a Denial of Service (DoS) condition. By continuously sending this specific stream of genuine Layer 2 frames, an attacker can repeatedly crash the PFE, causing a sustained Denial of Service (DoS). This issue affects Juniper Networks Junos OS Evolved: All versions prior to 20.4R1-EVO. This issue does not affect Junos OS versions.

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

CWE-754

Affected software

No affected versions have been published.

Timeline

Published
Apr 22, 2021
Last modified
Jun 17, 2026
NVD status
Modified

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CVE-2021-0239: Medium severity, CVSS 6.5 | Vulnix