CVE-2019-0039

Junos OS: Login credentials are vulnerable to brute force attacks through the REST API

Description

If REST API is enabled, the Junos OS login credentials are vulnerable to brute force attacks. The high default connection limit of the REST API may allow an attacker to brute-force passwords using advanced scripting techniques. Additionally, administrators who do not enforce a strong password policy can increase the likelihood of success from brute force attacks. Affected releases are Juniper Networks Junos OS: 14.1X53 versions prior to 14.1X53-D49; 15.1 versions prior to 15.1F6-S12, 15.1R7-S3; 15.1X49 versions prior to 15.1X49-D160; 15.1X53 versions prior to 15.1X53-D236, 15.1X53-D495, 15.1X53-D591, 15.1X53-D69; 16.1 versions prior to 16.1R3-S10, 16.1R4-S12, 16.1R6-S6, 16.1R7-S3; 16.1X65 versions prior to 16.1X65-D49; 16.2 versions prior to 16.2R2-S7; 17.1 versions prior to 17.1R2-S10, 17.1R3; 17.2 versions prior to 17.2R1-S8, 17.2R3-S1; 17.3 versions prior to 17.3R3-S2; 17.4 versions prior to 17.4R1-S6, 17.4R2-S2; 18.1 versions prior to 18.1R2-S4, 18.1R3-S1; 18.2 versions prior to 18.2R1-S5; 18.2X75 versions prior to 18.2X75-D30; 18.3 versions prior to 18.3R1-S1.

Remediation

Solution:

  • The following software releases have been updated to resolve this specific issue: Junos OS 14.1X53-D49, 15.1F6-S12, 15.1R7-S3, 15.1X49-D160, 15.1X53-D236, 15.1X53-D495, 15.1X53-D591, 15.1X53-D69, 16.1R3-S10, 16.1R4-S12, 16.1R6-S6, 16.1R7-S3, 16.1X65-D49, 16.2R2-S7, 17.1R2-S10, 17.1R3, 17.2R1-S8, 17.2R3-S1, 17.3R3-S2, 17.4R1-S6, 17.4R2-S2, 18.1R2-S4, 18.1R3-S1, 18.2R1-S5, 18.2X75-D30, 18.3R1-S1, 18.4R1, and all subsequent releases.

Workaround:

  • Setting a connection limit on REST API may help mitigate this issue. set system services rest control connection-limit 100 Use access lists or firewall filters to limit API access to the device only from trusted hosts.

Category

8.1
CVSS
Severity: High
CVSS 3.1 •
CVSS 3.0 •
CVSS 2.0 •
EPSS 0.29%
Vendor Advisory juniper.net
Affected: Juniper Networks Junos OS
Published at:
Updated at:

References

Link Tags
https://kb.juniper.net/JSA10928 mitigation vendor advisory
http://www.securityfocus.com/bid/107899 broken link third party advisory vdb entry

Frequently Asked Questions

What is the severity of CVE-2019-0039?
CVE-2019-0039 has been scored as a high severity vulnerability.
How to fix CVE-2019-0039?
To fix CVE-2019-0039: The following software releases have been updated to resolve this specific issue: Junos OS 14.1X53-D49, 15.1F6-S12, 15.1R7-S3, 15.1X49-D160, 15.1X53-D236, 15.1X53-D495, 15.1X53-D591, 15.1X53-D69, 16.1R3-S10, 16.1R4-S12, 16.1R6-S6, 16.1R7-S3, 16.1X65-D49, 16.2R2-S7, 17.1R2-S10, 17.1R3, 17.2R1-S8, 17.2R3-S1, 17.3R3-S2, 17.4R1-S6, 17.4R2-S2, 18.1R2-S4, 18.1R3-S1, 18.2R1-S5, 18.2X75-D30, 18.3R1-S1, 18.4R1, and all subsequent releases.
Is CVE-2019-0039 being actively exploited in the wild?
As for now, there are no information to confirm that CVE-2019-0039 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-2019-0039?
CVE-2019-0039 affects Juniper Networks Junos OS.
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