CVE-2022-22248

An Incorrect Permission Assignment vulnerability in shell processing of Juniper Networks Junos OS Evolved allows a low-privileged local user to modify the contents of a configuration file which could cause another user to execute arbitrary commands within the context of the follow-on users session. If the follow-on user is a high-privileged administrator, the attacker could leverage this vulnerability to take complete control of the target system. While this issue is triggered by a user, other than the attacker, accessing the Junos shell, an attacker simply requires Junos CLI access to exploit this vulnerability. This issue affects Juniper Networks Junos OS Evolved: 20.4-EVO versions prior to 20.4R3-S1-EVO; All versions of 21.1-EVO; 21.2-EVO versions prior to 21.2R3-EVO; 21.3-EVO versions prior to 21.3R2-EVO. This issue does not affect Juniper Networks Junos OS Evolved versions prior to 19.2R1-EVO.

Weakness

The product specifies permissions for a security-critical resource in a way that allows that resource to be read or modified by unintended actors.

Affected Software

Potential Mitigations

• Run the code in a “jail” or similar sandbox environment that enforces strict boundaries between the process and the operating system. This may effectively restrict which files can be accessed in a particular directory or which commands can be executed by the software.
• OS-level examples include the Unix chroot jail, AppArmor, and SELinux. In general, managed code may provide some protection. For example, java.io.FilePermission in the Java SecurityManager allows the software to specify restrictions on file operations.
• This may not be a feasible solution, and it only limits the impact to the operating system; the rest of the application may still be subject to compromise.
• Be careful to avoid CWE-243 and other weaknesses related to jails.

Related Attack Patterns

• https://cwe.mitre.org/data/definitions/1.html
• https://cwe.mitre.org/data/definitions/122.html
• https://cwe.mitre.org/data/definitions/127.html
• https://cwe.mitre.org/data/definitions/17.html
• https://cwe.mitre.org/data/definitions/180.html
• https://cwe.mitre.org/data/definitions/206.html
• https://cwe.mitre.org/data/definitions/234.html
• https://cwe.mitre.org/data/definitions/60.html
• https://cwe.mitre.org/data/definitions/61.html
• https://cwe.mitre.org/data/definitions/62.html
• https://cwe.mitre.org/data/definitions/642.html

References

• https://kb.juniper.net/JSA69905