CVE-2021-0219

Junos OS: Command injection vulnerability in 'request system software' CLI command

Description

A command injection vulnerability in install package validation subsystem of Juniper Networks Junos OS that may allow a locally authenticated attacker with privileges to execute commands with root privilege. To validate a package in Junos before installation, an administrator executes the command 'request system software add validate-on-host' via the CLI. An attacker with access to this CLI command may be able to exploit this vulnerability. This issue affects Juniper Networks Junos OS: all versions prior to 17.3R3-S10; 17.4 versions prior to 17.4R2-S12, 17.4R3-S3; 18.1 versions prior to 18.1R3-S11; 18.2 versions prior to 18.2R2-S8, 18.2R3-S6; 18.3 versions prior to 18.3R3-S4; 18.4 versions prior to 18.4R1-S8, 18.4R2-S7, 18.4R3-S6; 19.1 versions prior to 19.1R1-S6, 19.1R2-S2, 19.1R3-S3; 19.2 versions prior to 19.2R3-S1; 19.3 versions prior to 19.3R2-S5, 19.3R3-S1; 19.4 versions prior to 19.4R2-S2, 19.4R3-S1; 20.1 versions prior to 20.1R2; 20.2 versions prior to 20.2R1-S2, 20.2R2; 20.3 versions prior to 20.3R1-S1, 20.3R2.

Remediation

Solution:

  • The following software releases have been updated to resolve this specific issue: Junos OS: 17.3R3-S10, 17.4R2-S12, 17.4R3-S3, 18.1R3-S11, 18.2R2-S8, 18.2R3-S6, 18.2X75-D34, 18.3R3-S4, 18.4R1-S8, 18.4R2-S7, 18.4R3-S6, 19.1R1-S6, 19.1R2-S2, 19.1R3-S3, 19.2R3-S1, 19.3R2-S5, 19.3R3-S1, 19.4R2-S2, 19.4R3-S1, 20.1R2, 20.2R1-S2, 20.2R2, 20.3R1-S1, 20.3R2, 20.4R1, and all subsequent releases.

Workaround:

  • Use access lists or firewall filters to limit CLI access to the device only from trusted, administrative networks or hosts. Limit access to the Junos OS CLI to only trusted system administrators. Restrict access to the 'request system software add validate-on-host' command.

Category

6.7
CVSS
Severity: Medium
CVSS 3.1 •
CVSS 2.0 •
EPSS 0.04%
Vendor Advisory juniper.net
Affected: Juniper Networks Junos OS
Published at:
Updated at:

References

Link Tags
https://kb.juniper.net/JSA11109 vendor advisory

Frequently Asked Questions

What is the severity of CVE-2021-0219?
CVE-2021-0219 has been scored as a medium severity vulnerability.
How to fix CVE-2021-0219?
To fix CVE-2021-0219: The following software releases have been updated to resolve this specific issue: Junos OS: 17.3R3-S10, 17.4R2-S12, 17.4R3-S3, 18.1R3-S11, 18.2R2-S8, 18.2R3-S6, 18.2X75-D34, 18.3R3-S4, 18.4R1-S8, 18.4R2-S7, 18.4R3-S6, 19.1R1-S6, 19.1R2-S2, 19.1R3-S3, 19.2R3-S1, 19.3R2-S5, 19.3R3-S1, 19.4R2-S2, 19.4R3-S1, 20.1R2, 20.2R1-S2, 20.2R2, 20.3R1-S1, 20.3R2, 20.4R1, and all subsequent releases.
Is CVE-2021-0219 being actively exploited in the wild?
As for now, there are no information to confirm that CVE-2021-0219 is being actively exploited. According to its EPSS score, there is a ~0% probability that this vulnerability will be exploited by malicious actors in the next 30 days.
What software or system is affected by CVE-2021-0219?
CVE-2021-0219 affects Juniper Networks Junos OS.
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