CVE-2022-22167

Junos OS: SRX Series: If no-syn-check is enabled, traffic classified as UNKNOWN gets permitted by pre-id-default-policy

Description

A traffic classification vulnerability in Juniper Networks Junos OS on the SRX Series Services Gateways may allow an attacker to bypass Juniper Deep Packet Inspection (JDPI) rules and access unauthorized networks or resources, when 'no-syn-check' is enabled on the device. While JDPI correctly classifies out-of-state asymmetric TCP flows as the dynamic-application UNKNOWN, this classification is not provided to the policy module properly and hence traffic continues to use the pre-id-default-policy, which is more permissive, causing the firewall to allow traffic to be forwarded that should have been denied. This issue only occurs when 'set security flow tcp-session no-syn-check' is configured on the device. This issue affects Juniper Networks Junos OS on SRX Series: 18.4 versions prior to 18.4R2-S10, 18.4R3-S10; 19.1 versions prior to 19.1R3-S8; 19.2 versions prior to 19.2R1-S8, 19.2R3-S4; 19.3 versions prior to 19.3R3-S3; 19.4 versions prior to 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 prior to 20.4R2-S2, 20.4R3; 21.1 versions prior to 21.1R2-S2, 21.1R3; 21.2 versions prior to 21.2R2. This issue does not affect Juniper Networks Junos OS versions prior to 18.4R1.

Remediation

Solution:

  • The following software releases have been updated to resolve this specific issue: 18.4R2-S10, 18.4R3-S10, 19.1R3-S8, 19.2R1-S8, 19.2R3-S4, 19.3R3-S3, 19.4R3-S5, 20.1R3-S1, 20.2R3-S2, 20.3R3-S1, 20.4R2-S2, 20.4R3, 21.1R2-S2, 21.1R3, 21.2R2, 21.3R1, and all subsequent releases.

Workaround:

  • Any of the following workarounds will mitigate this issue: 1. Remove 'security flow tcp-session no-syn-check' from the configuration. 2: Enable AppID cache configuration: set services application-identification application-system-cache security-services

Category

7.2
CVSS
Severity: High
CVSS 3.1 •
CVSS 2.0 •
EPSS 0.26%
Vendor Advisory juniper.net
Affected: Juniper Networks Junos OS
Affected: Juniper Networks Junos OS
Published at:
Updated at:

References

Link Tags
https://kb.juniper.net/JSA11265 vendor advisory

Frequently Asked Questions

What is the severity of CVE-2022-22167?
CVE-2022-22167 has been scored as a high severity vulnerability.
How to fix CVE-2022-22167?
To fix CVE-2022-22167: The following software releases have been updated to resolve this specific issue: 18.4R2-S10, 18.4R3-S10, 19.1R3-S8, 19.2R1-S8, 19.2R3-S4, 19.3R3-S3, 19.4R3-S5, 20.1R3-S1, 20.2R3-S2, 20.3R3-S1, 20.4R2-S2, 20.4R3, 21.1R2-S2, 21.1R3, 21.2R2, 21.3R1, and all subsequent releases.
Is CVE-2022-22167 being actively exploited in the wild?
As for now, there are no information to confirm that CVE-2022-22167 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-2022-22167?
CVE-2022-22167 affects Juniper Networks Junos OS, Juniper Networks Junos OS.
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