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vulnerability

Juniper Junos OS: 2021-10 Security Bulletin: Junos OS and Junos OS Evolved: In Point to MultiPoint (P2MP) scenarios receipt of various crafted packets causes RPD to core. (JSA11251) (CVE-2021-31383)

Severity
4
CVSS
(AV:N/AC:M/Au:N/C:N/I:N/A:P)
Published
Oct 19, 2021
Added
Mar 21, 2022
Modified
Mar 27, 2026

Description

In Point to MultiPoint (P2MP) scenarios within established sessions between network or adjacent neighbors the improper use of a source to destination copy write operation combined with a Stack-based Buffer Overflow on certain specific packets processed by the routing protocol daemon (RPD) of Juniper Networks Junos OS and Junos OS Evolved sent by a remote unauthenticated network attacker causes the RPD to crash causing a Denial of Service (DoS). Continued receipt and processing of these packets will create a sustained Denial of Service (DoS) condition. This issue affects: Juniper Networks Junos OS 19.2 versions prior to 19.2R3-S2; 19.3 versions prior to 19.3R2-S6, 19.3R3-S2; 19.4 versions prior to 19.4R1-S4, 19.4R2-S4, 19.4R3-S3; 20.1 versions prior to 20.1R2-S2, 20.1R3; 20.2 versions prior to 20.2R2-S3, 20.2R3; 20.3 versions prior to 20.3R2. This issue does not affect Juniper Networks Junos OS versions prior to 19.2R1. Juniper Networks Junos OS Evolved 20.1 versions prior to 20.1R3-EVO; 20.2 versions prior to 20.2R3-EVO; 20.3 versions prior to 20.3R2-EVO.

Solution

juniper-junos-os-upgrade-latest
Title
Rapid7 Labs

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