Juniper Junos OS Vulnerability (JSA11218)

high Nessus Plugin ID 154111


The remote device is missing a vendor-supplied security patch.


The version of Junos OS installed on the remote host is affected by a vulnerability as referenced in the JSA11218 advisory.

- An Improper Handling of Exceptional Conditions vulnerability in Juniper Networks Junos OS and Junos OS Evolved allows an attacker to inject a specific BGP update, causing the routing protocol daemon (RPD) to crash and restart, leading to a Denial of Service (DoS). Continued receipt and processing of the BGP update will create a sustained Denial of Service (DoS) condition. This issue affects very specific versions of Juniper Networks Junos OS: 19.3R3-S2; 19.4R3-S3; 20.2 versions 20.2R2-S3 and later, prior to 20.2R3-S2; 20.3 versions 20.3R2 and later, prior to 20.3R3; 20.4 versions 20.4R2 and later, prior to 20.4R3; 21.1 versions prior to 21.1R2. Juniper Networks Junos OS 20.1 is not affected by this issue. This issue also affects Juniper Networks Junos OS Evolved: All versions prior to 20.4R2-S3-EVO, 20.4R3-EVO;
21.1-EVO versions prior to 21.1R2-EVO; 21.2-EVO versions prior to 21.2R2-EVO. (CVE-2021-31353)

Note that Nessus has not tested for this issue but has instead relied only on the application's self-reported version number.


Apply the relevant Junos software release referenced in Juniper advisory JSA11218

See Also

Plugin Details

Severity: High

ID: 154111

File Name: juniper_jsa11218.nasl

Version: 1.6

Type: combined

Published: 10/13/2021

Updated: 11/28/2023

Supported Sensors: Nessus

Risk Information


Risk Factor: Medium

Score: 4.4


Risk Factor: Medium

Base Score: 5

Temporal Score: 3.9

Vector: CVSS2#AV:N/AC:L/Au:N/C:N/I:N/A:P

CVSS Score Source: CVE-2021-31353


Risk Factor: High

Base Score: 7.5

Temporal Score: 6.7

Vector: CVSS:3.0/AV:N/AC:L/PR:N/UI:N/S:U/C:N/I:N/A:H

Temporal Vector: CVSS:3.0/E:P/RL:O/RC:C

Vulnerability Information

CPE: cpe:/o:juniper:junos

Required KB Items: Host/Juniper/JUNOS/Version

Exploit Available: true

Exploit Ease: Exploits are available

Patch Publication Date: 10/13/2021

Vulnerability Publication Date: 10/13/2021

Reference Information

CVE: CVE-2021-31353

IAVA: 2021-A-0478-S

JSA: JSA11218