6.5
MEDIUM
CVE-2021-0239
Juniper Networks Junos OS Evolved Layer 2 Frame Crash DoS Vulnerability
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.

INFO

Published Date :

April 22, 2021, 8:15 p.m.

Last Modified :

April 27, 2021, 5:45 p.m.

Remotely Exploitable :

No

Impact Score :

3.6

Exploitability Score :

2.8
Affected Products

The following products are affected by CVE-2021-0239 vulnerability. Even if cvefeed.io is aware of the exact versions of the products that are affected, the information is not represented in the table below.

ID Vendor Product Action
1 Juniper junos_os_evolved
References to Advisories, Solutions, and Tools

Here, you will find a curated list of external links that provide in-depth information, practical solutions, and valuable tools related to CVE-2021-0239.

URL Resource
https://kb.juniper.net/JSA11134 Vendor Advisory

We scan GitHub repositories to detect new proof-of-concept exploits. Following list is a collection of public exploits and proof-of-concepts, which have been published on GitHub (sorted by the most recently updated).

Results are limited to the first 15 repositories due to potential performance issues.

The following list is the news that have been mention CVE-2021-0239 vulnerability anywhere in the article.

The following table lists the changes that have been made to the CVE-2021-0239 vulnerability over time.

Vulnerability history details can be useful for understanding the evolution of a vulnerability, and for identifying the most recent changes that may impact the vulnerability's severity, exploitability, or other characteristics.

  • CVE Modified by [email protected]

    May. 14, 2024

    Action Type Old Value New Value
  • Initial Analysis by [email protected]

    Apr. 27, 2021

    Action Type Old Value New Value
    Added CVSS V2 NIST (AV:A/AC:L/Au:N/C:N/I:N/A:C)
    Added CVSS V3.1 NIST AV:A/AC:L/PR:N/UI:N/S:U/C:N/I:N/A:H
    Changed Reference Type https://kb.juniper.net/JSA11134 No Types Assigned https://kb.juniper.net/JSA11134 Vendor Advisory
    Added CWE NIST CWE-754
    Added CPE Configuration OR *cpe:2.3:o:juniper:junos_os_evolved:20.4:r1:*:*:*:*:*:*
EPSS is a daily estimate of the probability of exploitation activity being observed over the next 30 days. Following chart shows the EPSS score history of the vulnerability.
CWE - Common Weakness Enumeration

While CVE identifies specific instances of vulnerabilities, CWE categorizes the common flaws or weaknesses that can lead to vulnerabilities. CVE-2021-0239 is associated with the following CWEs:

Common Attack Pattern Enumeration and Classification (CAPEC)

Common Attack Pattern Enumeration and Classification (CAPEC) stores attack patterns, which are descriptions of the common attributes and approaches employed by adversaries to exploit the CVE-2021-0239 weaknesses.

Exploit Prediction

EPSS is a daily estimate of the probability of exploitation activity being observed over the next 30 days.

0.06 }} 0.01%

score

0.22873

percentile

CVSS31 - Vulnerability Scoring System
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