SB2022011701 - Traffic classification vulnerabilities in Juniper Junos OS
Published: January 17, 2022
Breakdown by Severity
- Low
- Medium
- High
- Critical
Description
This security bulletin contains information about 2 secuirty vulnerabilities.
1) Security features bypass (CVE-ID: CVE-2022-22157)
The vulnerability allows a remote attacker by bypass implemented security restrictions.
The vulnerability exists due to a traffic classification issue on the SRX Series Services Gateways when 'no-syn-check' is enabled on the device. JDPI incorrectly classifies out-of-state asymmetric TCP flows as the dynamic-application INCONCLUSIVE instead of UNKNOWN, which is more permissive, causing the firewall to allow traffic to be forwarded that should have been denied. A remote attacker can bypass Juniper Deep Packet Inspection (JDPI) rules and access unauthorized networks or resources.
Note, this issue only occurs when 'set security flow tcp-session no-syn-check' is configured on the device.
2) Security features bypass (CVE-ID: CVE-2022-22167)
The vulnerability allows a remote attacker to bypass implemented security restrictions.
The vulnerability exists due to a traffic classification issue on the SRX Series Services Gateways 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. A remote attacker can bypass Juniper Deep Packet Inspection (JDPI) rules and access unauthorized networks or resources.
Note, the issue only occurs when 'set security flow tcp-session no-syn-check' is configured on the device.
Remediation
Install update from vendor's website.