CVE-2021-31382

Junos OS: PTX1000 System, PTX10002-60C System: After upgrading, configured firewall filters may be applied on incorrect interfaces

Description

On PTX1000 System, PTX10002-60C System, after upgrading to an affected release, a Race Condition vulnerability between the chassis daemon (chassisd) and firewall process (dfwd) of Juniper Networks Junos OS, may update the device's interfaces with incorrect firewall filters. This issue only occurs when upgrading the device to an affected version of Junos OS. Interfaces intended to have protections may have no protections assigned to them. Interfaces with one type of protection pattern may have alternate protections assigned to them. Interfaces intended to have no protections may have protections assigned to them. These firewall rule misassignments may allow genuine traffic intended to be stopped at the interface to propagate further, potentially causing disruptions in services by propagating unwanted traffic. An attacker may be able to take advantage of these misassignments. This issue affects Juniper Networks Junos OS on PTX1000 System: 17.2 versions 17.2R1 and later versions prior to 17.3 versions prior to 17.3R3-S12; 17.4 versions prior to 17.4R3-S5; 18.1 versions prior to 18.1R3-S13; 18.2 versions prior to 18.2R3-S8; 18.3 versions prior to 18.3R3-S5; 18.4 versions prior to 18.4R1-S8, 18.4R2-S8, 18.4R3-S8; 19.1 versions prior to 19.1R3-S5; 19.2 versions prior to 19.2R3-S2; 19.3 versions prior to 19.3R2-S6, 19.3R3-S3; 19.4 versions prior to 19.4R2-S4, 19.4R3-S3; 20.1 versions prior to 20.1R3; 20.2 versions prior to 20.2R2-S3, 20.2R3; 20.3 versions prior to 20.3R2-S1, 20.3R3; 20.4 versions prior to 20.4R1-S1, 20.4R2. This issue does not affect Juniper Networks Junos OS prior to version 17.2R1 on PTX1000 System. This issue affects Juniper Networks Junos OS on PTX10002-60C System: 18.2 versions 18.2R1 and later versions prior to 18.4 versions prior to 18.4R3-S9; 19.1 versions later than 19.1R1 prior to 19.4 versions prior to 19.4R2-S5, 19.4R3-S5; 20.1 versions prior to 20.1R3-S1; 20.2 versions prior to 20.2R3-S2; 20.3 versions prior to 20.3R3-S1; 20.4 versions 20.4R1 and later versions prior to 21.1 versions prior to 21.1R2; 21.2 versions 21.2R1 and later versions prior to 21.3 versions prior to 21.3R2. This issue does not affect Juniper Networks Junos OS prior to version 18.2R1 on PTX10002-60C System. This issue impacts all filter families (inet, inet6, etc.) and all loopback filters. It does not rely upon the location where a filter is set, impacting both logical and physical interfaces.

Remediation

Solution:

  • The following software releases have been updated to resolve this specific issue: Junos OS on PTX1000 System: 17.3R3-S12, 18.1R3-S13, 18.2R3-S8, 18.3R3-S5, 18.4R1-S8, 18.4R2-S8, 18.4R3-S8, 19.1R3-S5, 19.2R3-S2, 19.3R2-S6, 19.3R3-S3, 19.4R2-S4, 19.4R3-S3, 20.1R3, 20.2R2-S3, 20.2R3, 20.3R2-S1, 20.3R3, 20.4R1-S1, 20.4R2, 21.1R1, and all subsequent releases. Junos OS on PTX10002-60C System: 18.4R3-S9, 19.4R2-S5, 19.4R3-S5, 20.1R3-S1, 20.2R3-S2, 20.3R3-S1, 21.1R2, 21.3R2, 21.4R1, and all subsequent releases.

Workaround:

  • Restart the firewall daemon after the system has rebooted after the upgrade.

Category

6.5
CVSS
Severity: Medium
CVSS 3.1 •
CVSS 2.0 •
EPSS 0.22%
Vendor Advisory juniper.net Vendor Advisory juniper.net
Affected: Juniper Networks Junos OS
Affected: Juniper Networks Junos OS
Published at:
Updated at:

References

Frequently Asked Questions

What is the severity of CVE-2021-31382?
CVE-2021-31382 has been scored as a medium severity vulnerability.
How to fix CVE-2021-31382?
To fix CVE-2021-31382: The following software releases have been updated to resolve this specific issue: Junos OS on PTX1000 System: 17.3R3-S12, 18.1R3-S13, 18.2R3-S8, 18.3R3-S5, 18.4R1-S8, 18.4R2-S8, 18.4R3-S8, 19.1R3-S5, 19.2R3-S2, 19.3R2-S6, 19.3R3-S3, 19.4R2-S4, 19.4R3-S3, 20.1R3, 20.2R2-S3, 20.2R3, 20.3R2-S1, 20.3R3, 20.4R1-S1, 20.4R2, 21.1R1, and all subsequent releases. Junos OS on PTX10002-60C System: 18.4R3-S9, 19.4R2-S5, 19.4R3-S5, 20.1R3-S1, 20.2R3-S2, 20.3R3-S1, 21.1R2, 21.3R2, 21.4R1, and all subsequent releases.
Is CVE-2021-31382 being actively exploited in the wild?
As for now, there are no information to confirm that CVE-2021-31382 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-2021-31382?
CVE-2021-31382 affects Juniper Networks Junos OS, Juniper Networks Junos OS.
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