6.5
MEDIUM
CVE-2021-31363
Juniper Networks Junos OS and Junos OS Evolved MPLS P2MP Loop with Unreachable Exit Condition Remote Denial of Service
Description

In an MPLS P2MP environment a Loop with Unreachable Exit Condition vulnerability in the routing protocol daemon (RPD) of Juniper Networks Junos OS and Junos OS Evolved allows an unauthenticated adjacent attacker to cause high load on RPD which in turn may lead to routing protocol flaps. If a system with sensor-based-stats enabled receives a specific LDP FEC this can lead to the above condition. Continued receipted of such an LDP FEC will create a sustained Denial of Service (DoS) condition. This issue affects: Juniper Networks Junos OS 19.2 version 19.2R2 and later versions prior to 19.2R3-S3; 19.3 versions prior to 19.3R2-S6, 19.3R3-S2; 19.4 versions prior to 19.4R1-S4, 19.4R2-S4, 19.4R3-S2; 20.1 versions prior to 20.1R2-S1, 20.1R3; 20.2 versions prior to 20.2R2-S1, 20.2R3; 20.3 versions prior to 20.3R1-S2, 20.3R2. This issue does not affect Juniper Networks Junos OS versions prior to 19.2R2. Juniper Networks Junos OS Evolved All versions prior to 20.1R2-S3-EVO; 20.3 versions prior to 20.3R1-S2-EVO.

INFO

Published Date :

Oct. 19, 2021, 7:15 p.m.

Last Modified :

Oct. 25, 2021, 5:14 p.m.

Remotely Exploitable :

No

Impact Score :

3.6

Exploitability Score :

2.8
Affected Products

The following products are affected by CVE-2021-31363 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
2 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-2021-31363.

URL Resource
https://kb.juniper.net/JSA11225 Patch 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-2021-31363 vulnerability anywhere in the article.

The following table lists the changes that have been made to the CVE-2021-31363 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]

    Oct. 25, 2021

    Action Type Old Value New Value
    Added CVSS V2 NIST (AV:A/AC:L/Au:N/C:N/I:N/A:P)
    Changed Reference Type https://kb.juniper.net/JSA11225 No Types Assigned https://kb.juniper.net/JSA11225 Patch, Vendor Advisory
    Added CWE NIST CWE-835
    Added CPE Configuration OR *cpe:2.3:o:juniper:junos:19.2:r2:*:*:*:*:*:* *cpe:2.3:o:juniper:junos:19.2:r2-s1:*:*:*:*:*:* *cpe:2.3:o:juniper:junos:19.2:r3:*:*:*:*:*:* *cpe:2.3:o:juniper:junos:19.2:r3-s1:*:*:*:*:*:* *cpe:2.3:o:juniper:junos:19.2:r3-s2:*:*:*:*:*:* *cpe:2.3:o:juniper:junos:19.3:-:*:*:*:*:*:* *cpe:2.3:o:juniper:junos:19.3:r1:*:*:*:*:*:* *cpe:2.3:o:juniper:junos:19.3:r1-s1:*:*:*:*:*:* *cpe:2.3:o:juniper:junos:19.3:r2:*:*:*:*:*:* *cpe:2.3:o:juniper:junos:19.3:r2-s1:*:*:*:*:*:* *cpe:2.3:o:juniper:junos:19.3:r2-s2:*:*:*:*:*:* *cpe:2.3:o:juniper:junos:19.3:r2-s3:*:*:*:*:*:* *cpe:2.3:o:juniper:junos:19.3:r2-s4:*:*:*:*:*:* *cpe:2.3:o:juniper:junos:19.3:r2-s5:*:*:*:*:*:* *cpe:2.3:o:juniper:junos:19.3:r3-s2:*:*:*:*:*:* *cpe:2.3:o:juniper:junos:19.4:r1:*:*:*:*:*:* *cpe:2.3:o:juniper:junos:19.4:r1-s1:*:*:*:*:*:* *cpe:2.3:o:juniper:junos:19.4:r1-s2:*:*:*:*:*:* *cpe:2.3:o:juniper:junos:19.4:r1-s3:*:*:*:*:*:* *cpe:2.3:o:juniper:junos:19.4:r2-s4:*:*:*:*:*:* *cpe:2.3:o:juniper:junos:19.4:r3-s2:*:*:*:*:*:* *cpe:2.3:o:juniper:junos:20.1:r1:*:*:*:*:*:* *cpe:2.3:o:juniper:junos:20.1:r1-s1:*:*:*:*:*:* *cpe:2.3:o:juniper:junos:20.1:r1-s2:*:*:*:*:*:* *cpe:2.3:o:juniper:junos:20.1:r1-s3:*:*:*:*:*:* *cpe:2.3:o:juniper:junos:20.1:r1-s4:*:*:*:*:*:* *cpe:2.3:o:juniper:junos:20.1:r2:*:*:*:*:*:* *cpe:2.3:o:juniper:junos:20.1:r3:*:*:*:*:*:* *cpe:2.3:o:juniper:junos:20.2:r1:*:*:*:*:*:* *cpe:2.3:o:juniper:junos:20.2:r1-s1:*:*:*:*:*:* *cpe:2.3:o:juniper:junos:20.2:r1-s2:*:*:*:*:*:* *cpe:2.3:o:juniper:junos:20.2:r1-s3:*:*:*:*:*:* *cpe:2.3:o:juniper:junos:20.2:r2:*:*:*:*:*:* *cpe:2.3:o:juniper:junos:20.2:r3:*:*:*:*:*:* *cpe:2.3:o:juniper:junos:20.3:r1:*:*:*:*:*:* *cpe:2.3:o:juniper:junos:20.3:r1-s1:*:*:*:*:*:* *cpe:2.3:o:juniper:junos:20.3:r2:*:*:*:*:*:* *cpe:2.3:o:juniper:junos_os_evolved:20.1:r1:*:*:*:*:*:* *cpe:2.3:o:juniper:junos_os_evolved:20.1:r1-s1:*:*:*:*:*:* *cpe:2.3:o:juniper:junos_os_evolved:20.1:r2:*:*:*:*:*:* *cpe:2.3:o:juniper:junos_os_evolved:20.1:r2-s1:*:*:*:*:*:* *cpe:2.3:o:juniper:junos_os_evolved:20.1:r2-s2:*:*:*:*:*:* *cpe:2.3:o:juniper:junos_os_evolved:20.2:r1:*:*:*:*:*:* *cpe:2.3:o:juniper:junos_os_evolved:20.2:r1-s1:*:*:*:*:*:* *cpe:2.3:o:juniper:junos_os_evolved:20.2:r2:*:*:*:*:*:* *cpe:2.3:o:juniper:junos_os_evolved:20.3:r1:*:*:*:*:*:* *cpe:2.3:o:juniper:junos_os_evolved:20.3:r1-s1:*:*:*:*:*:*
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-2021-31363 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-2021-31363 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

0.25152

percentile

CVSS31 - Vulnerability Scoring System
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