AUGUST 4, 2026
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Case File

CVE-2021-0239

MEDIUM · CVSS 6.5 EPSS 0.38%

Source: NVD + CISA KEV + EPSS (historical backfill) · Published 2021-04-22 · Last synced 2026-08-04

CyberRota Analysis

This is a medium severity vulnerability with a CVSS score of 6.5. It may lead to a denial-of-service condition.

CVE
CVE-2021-0239
Severity
MEDIUM
CVSS
6.5
EPSS
0.38%

Original NVD 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.

Related CVEs

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