CVE-2020-1637

Junos OS: SRX Series: Unified Access Control (UAC) bypass vulnerability

Description

A vulnerability in Juniper Networks SRX Series device configured as a Junos OS Enforcer device may allow a user to access network resources that are not permitted by a UAC policy. This issue might occur when the IP address range configured in the Infranet Controller (IC) is configured as an IP address range instead of an IP address/netmask. See the Workaround section for more detail. The Junos OS Enforcer CLI settings are disabled by default. This issue affects Juniper Networks Junos OS on SRX Series: 12.3X48 versions prior to 12.3X48-D100; 15.1X49 versions prior to 15.1X49-D210; 17.3 versions prior to 17.3R2-S5, 17.3R3-S8; 17.4 versions prior to 17.4R2-S9, 17.4R3-S1; 18.1 versions prior to 18.1R3-S10; 18.2 versions prior to 18.2R2-S7, 18.2R3-S3; 18.3 versions prior to 18.3R1-S7, 18.3R3-S2; 18.4 versions prior to 18.4R1-S6, 18.4R2-S4, 18.4R3-S1; 19.1 versions prior to 19.1R1-S4, 19.1R2-S1, 19.1R3; 19.2 versions prior to 19.2R1-S3, 19.2R2; 19.3 versions prior to 19.3R2-S1, 19.3R3; 19.4 versions prior to 19.4R1-S1, 19.4R2.

Remediation

Solution:

  • The following software releases have been updated to resolve this specific issue: 12.3X48-D100, 15.1X49-D210, 16.1R7-S7, 17.3R2-S5, 17.3R3-S8, 17.4R2-S9, 17.4R3-S1, 18.1R3-S10, 18.2R3-S3, 18.3R1-S7, 18.3R3-S2, 18.4R1-S6, 18.4R2-S4, 18.4R3-S1, 19.1R1-S4, 19.1R2-S1, 19.1R3, 19.2R1-S3, 19.2R2, 19.3R2-S1, 19.3R3, 19.4R1-S1, 19.4R2, 20.1R1, and all subsequent releases.

Workaround:

  • To avoid this issue, the IP address configuration in the IC Server should be configured as IP address/netmask, rather than an IP address range. For example: configure 10.0.0.0/25 instead of 10.0.0.1-127.

Categories

7.2
CVSS
Severity: High
CVSS 3.1 •
CVSS 2.0 •
EPSS 0.19%
Vendor Advisory juniper.net
Affected: Juniper Networks Junos OS
Published at:
Updated at:

References

Link Tags
https://kb.juniper.net/JSA11018 vendor advisory

Frequently Asked Questions

What is the severity of CVE-2020-1637?
CVE-2020-1637 has been scored as a high severity vulnerability.
How to fix CVE-2020-1637?
To fix CVE-2020-1637: The following software releases have been updated to resolve this specific issue: 12.3X48-D100, 15.1X49-D210, 16.1R7-S7, 17.3R2-S5, 17.3R3-S8, 17.4R2-S9, 17.4R3-S1, 18.1R3-S10, 18.2R3-S3, 18.3R1-S7, 18.3R3-S2, 18.4R1-S6, 18.4R2-S4, 18.4R3-S1, 19.1R1-S4, 19.1R2-S1, 19.1R3, 19.2R1-S3, 19.2R2, 19.3R2-S1, 19.3R3, 19.4R1-S1, 19.4R2, 20.1R1, and all subsequent releases.
Is CVE-2020-1637 being actively exploited in the wild?
As for now, there are no information to confirm that CVE-2020-1637 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-2020-1637?
CVE-2020-1637 affects Juniper Networks Junos OS.
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