Description

A Use After Free vulnerability in the chassis daemon (chassisd) of Juniper Networks Junos OS and Junos OS Evolved allows a network-based attacker authenticated with low privileges to cause a Denial-of-Service (DoS). When telemetry collectors are frequently subscribing and unsubscribing to sensors continuously over a long period of time, telemetry-capable processes like chassisd, rpd or mib2d will crash and restart, which - depending on the process - can cause a complete outage until the system has recovered. This issue affects:  Junos OS:  * all versions before 22.4R3-S8, * 23.2 versions before 23.2R2-S5, * 23.4 versions before 23.4R2; Junos OS Evolved: * all versions before 22.4R3-S8-EVO, * 23.2 versions before 23.2R2-S5-EVO, * 23.4 versions before 23.4R2-EVO.

INFO

Published Date :

2026-01-15T20:28:29.656Z

Last Modified :

2026-01-15T20:55:25.182Z

Source :

juniper
AFFECTED PRODUCTS

The following products are affected by CVE-2026-21921 vulnerability.

Vendors Products
Juniper Networks
  • Junos Os
  • Junos Os Evolved
REFERENCES

Here, you will find a curated list of external links that provide in-depth information to CVE-2026-21921.

URL Resource
https://kb.juniper.net/JSA106021 cve-icon cve-icon
https://supportportal.juniper.net/JSA106021 cve-icon cve-icon
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CVSS Vulnerability Scoring System

Detailed values of each vector for above chart.
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Privileges Required
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SS Confidentiality
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Detailed values of each vector for above chart.
Attack Vector
Attack Complexity
Privileges Required
User Interaction
Scope
Confidentiality Impact
Integrity Impact
Availability Impact