CVE-2021-0239: 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…

PriorityP427medium6.5CVSS 3.1

AVAACLPRNUINSUCNINAH

EPSS

0.38%

30.7th percentile

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.

Affected

3 ranges

Vendor	Product	Version range	Fixed in
juniper	junos_os	—	—
juniper	junos_os_evolved	—	—
juniper_networks	junos_os_evolved	>= unspecified < 20.4R1-EVO	20.4R1-EVO

CVSS provenance

nvdv3.16.5MEDIUMCVSS:3.1/AV:A/AC:L/PR:N/UI:N/S:U/C:N/I:N/A:H

nvdv2.06.1MEDIUMAV:A/AC:L/Au:N/C:N/I:N/A:C

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