2020-10 Security Bulletin: Junos OS: SRX1500, vSRX, SRX4K, NFX150, NFX250: Denial of service vulnerability executing local CLI command (CVE-2020-1682)

Product Affected:

This issue affects Junos OS 15.1X49, 17.4, 18.1, 18.2, 18.3, 18.4, 19.1, 19.2. Affected platforms: NFX150, NFX250, SRX1500, SRX4100, SRX4200, vSRX.

Problem:

An input validation vulnerability exists in Juniper Networks Junos OS, allowing an attacker to crash the srxpfe process, causing a Denial of Service (DoS) through the use of specific maintenance commands. The srxpfe process restarts automatically, but continuous execution of the commands could lead to an extended Denial of Service condition.

This issue only affects the SRX1500, SRX4100, SRX4200, NFX150, NFX250, and vSRX-based platforms. No other products or platforms are affected by this vulnerability.

This issue affects Juniper Networks Junos OS:

15.1X49 versions prior to 15.1X49-D220 on SRX1500, SRX4100, SRX4200, vSRX;
17.4 versions prior to 17.4R3-S3 on SRX1500, SRX4100, SRX4200, vSRX;
18.1 versions prior to 18.1R3-S11 on SRX1500, SRX4100, SRX4200, vSRX, NFX150;
18.2 versions prior to 18.2R3-S5 on SRX1500, SRX4100, SRX4200, vSRX, NFX150, NFX250;
18.3 versions prior to 18.3R2-S4, 18.3R3-S3 on SRX1500, SRX4100, SRX4200, vSRX, NFX150, NFX250;
18.4 versions prior to 18.4R2-S5, 18.4R3-S4 on SRX1500, SRX4100, SRX4200, vSRX, NFX150, NFX250;
19.1 versions prior to 19.1R3-S2 on SRX1500, SRX4100, SRX4200, vSRX, NFX150, NFX250;
19.2 versions prior to 19.2R1-S5, 19.2R3 on SRX1500, SRX4100, SRX4200, vSRX, NFX150, NFX250.

This issue does not affect Junos OS 19.3 or any subsequent version.

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

This issue was discovered during external security research.

This issue has been assigned CVE-2020-1682.

Solution:

The following software releases have been updated to resolve this specific issue: Junos OS 15.1X49-D220, 17.4R3-S3, 18.1R3-S11, 18.2R3-S5, 18.3R2-S4, 18.3R3-S3, 18.4R2-S5, 18.4R3-S4, 19.1R3-S2, 19.2R1-S5, and 19.2R3.
Note: This fix has also been proactively committed into other releases that might not be vulnerable to this issue.

This issue is being tracked as 1486905.

Workaround:

Use access lists or firewall filters to limit access to the device only from trusted hosts and trusted administrators.

Implementation:

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

Modification History:

2020-10-14: Initial Publication
2020-10-21: Added NFX250 running Junos OS 18.2R1 or later.

CVSS Score:

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

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:

Juniper SIRT would like to acknowledge and thank The UK's National Cyber Security Centre (NCSC) for responsibly reporting this vulnerability.

Knowledge Base