CVE-2021-0253

Public Exploit
Junos OS: NFX Series: Local Command Execution Vulnerability in JDMD Leads to Privilege Escalation

Description

NFX Series devices using Juniper Networks Junos OS are susceptible to a local command execution vulnerability thereby allowing an attacker to elevate their privileges via the Junos Device Management Daemon (JDMD) process. This issue affects Juniper Networks Junos OS on NFX Series 17.2 version 17.2R1 and later versions prior to 18.3R3-S4; 18.4 versions prior to 18.4R2-S5, 18.4R3-S5; 19.1 versions prior to 19.1R1-S3; 19.2 version 19.1R2 and later versions prior to 19.2R3; 19.3 versions prior to 19.3R3; 19.4 versions prior to 19.4R2-S2. 19.4 versions 19.4R3 and above. This issue does not affect Juniper Networks Junos OS versions prior to 17.2R1. This issue does not affect the JDMD as used by Junos Node Slicing such as External Servers use in conjunction with Junos Node Slicing and In-Chassis Junos Node Slicing on MX480, MX960, MX2008, MX2010, MX2020.

Remediation

Solution:

  • The following software releases have been updated to resolve this specific issue: 18.3R3-S4, 18.4R2-S5, 18.4R3-S5, 19.1R3-S3, 19.2R3, 19.3R3, 19.4R2-S2, 20.1R1 and all subsequent releases.

Workaround:

  • There are no viable workarounds for this issue. To reduce the risk of exploitation of this issue, use access lists or firewall filters to limit access to only trusted administrative networks, hosts and users.

Category

7.8
CVSS
Severity: High
CVSS 3.1 •
CVSS 2.0 •
EPSS 0.44%
Vendor Advisory juniper.net
Affected: Juniper Networks Junos OS
Affected: Juniper Networks Junos OS
Published at:
Updated at:

References

Link Tags
https://kb.juniper.net/JSA11146 vendor advisory
https://github.com/orangecertcc/security-research/security/advisories/GHSA-vrf9-cjcp-rwcr third party advisory exploit

Frequently Asked Questions

What is the severity of CVE-2021-0253?
CVE-2021-0253 has been scored as a high severity vulnerability.
How to fix CVE-2021-0253?
To fix CVE-2021-0253: The following software releases have been updated to resolve this specific issue: 18.3R3-S4, 18.4R2-S5, 18.4R3-S5, 19.1R3-S3, 19.2R3, 19.3R3, 19.4R2-S2, 20.1R1 and all subsequent releases.
Is CVE-2021-0253 being actively exploited in the wild?
It is possible that CVE-2021-0253 is being exploited or will be exploited in a near future based on public information. 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-2021-0253?
CVE-2021-0253 affects Juniper Networks Junos OS, Juniper Networks Junos OS.
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