2021-01 Security Bulletin: Junos OS: Privilege escalation in J-Web due to arbitrary command and code execution via information disclosure from another users active session (CVE-2021-0210)

Product Affected:

This issue affects Junos OS 12.3, 17.3, 17.4, 18.1, 18.2, 18.3, 18.4, 19.1, 19.2, 19.3, 19.4, 20.1, 20.2.

Problem:

An Information Exposure vulnerability in J-Web of Juniper Networks Junos OS allows an unauthenticated attacker to elevate their privileges over the target system through opportunistic use of an authenticated users session.

This issue affects:

Juniper Networks Junos OS

12.3 versions prior to 12.3R12-S17;
17.3 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 18.2R3-S6;
18.3 versions prior to 18.3R2-S4, 18.3R3-S4;
18.4 versions prior to 18.4R2-S5, 18.4R3-S5;
19.1 versions prior to 19.1R1-S6, 19.1R2-S2, 19.1R3-S3;
19.2 versions prior to 19.2R1-S5, 19.2R3, 19.2R3-S1;
19.3 versions prior to 19.3R2-S4, 19.3R3;
19.4 versions prior to 19.4R1-S3, 19.4R2-S2, 19.4R3;
20.1 versions prior to 20.1R1-S4, 20.1R2;
20.2 versions prior to 20.2R1-S1, 20.2R2.

The following minimal configuration is required:

[system services web-management]

Juniper SIRT is not aware of any malicious exploitation of this vulnerability.

This issue was discovered during a external security research.

This issue has been assigned CVE-2021-0210.

Solution:

The following software releases have been updated to resolve this specific issue: 12.3R12-S17, 15.1R7-S8, 17.3R3-S10, 17.4R2-S12, 17.4R3-S3, 18.1R3-S11, 18.2R3-S6, 18.3R2-S4, 18.3R3-S4, 18.4R2-S5, 18.4R3-S5, 19.1R1-S6, 19.1R2-S2, 19.1R3-S3, 19.2R1-S5, 19.2R3, 19.2R3-S1, 19.3R2-S4, 19.3R3, 19.4R1-S3, 19.4R2-S2, 19.4R3, 20.1R1-S4, 20.1R2, 20.2R1-S1, 20.2R2, 20.3R1, and all subsequent releases.

This issue is being tracked as 1518212.

Workaround:

There are no known workarounds for this issue.

Implementation:

Software releases or updates are available for download at https://www.juniper.net/support/downloads/.

Modification History:

2021-01-13: Initial Publication.

CVSS Score:

6.8 (CVSS:3.1/AV:N/AC:H/PR:N/UI:R/S:U/C:H/I:H/A:N)

Severity Level:

Medium

Severity Assessment:

Information for how Juniper Networks uses CVSS can be found at KB 16446 "Common Vulnerability Scoring System (CVSS) and Juniper's Security Advisories."

Acknowledgements:

Lena David and Geoffrey Bertoli of Synacktiv (https://synacktiv.com)

Knowledge Base