Vulnerability identifier: #VU59625

Vulnerability risk: Medium

CVSSv3.1: 6.3 [CVSS:3.1/AV:N/AC:L/PR:N/UI:N/S:C/C:L/I:L/A:N/E:U/RL:O/RC:C]

CVE-ID: CVE-2022-22167

CWE-ID: CWE-254

Exploitation vector: Network

Exploit availability: No

Vulnerable software:
Juniper Junos OS
Operating systems & Components / Operating system

Vendor: Juniper Networks, Inc.

Description

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.

Mitigation
Install updates from vendor's website.

Vulnerable software versions

Juniper Junos OS: 19.1 - 19.1R3-S7, 19.1R1-S4, 18.4 - 18.4R3-S9, 18.4R1-S5, 18.4R2-S3, 19.2 - 19.2R3-S3, 19.2R1-S4, 21.1 - 21.1R2-S1, 20.3 - 20.3R3, 20.4 - 20.4R2-S1, 21.2R1 - 21.2R1-S2, 20.1 - 20.1R3, 19.4 - 19.4R3-S4, 19.4R1 - 19.4R1-S4, 19.3 - 19.3R3-S2, 19.3R1-S1, 19.3R2 - 19.3R2-S7, 20.2 - 20.2R3-S1

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External links
http://kb.juniper.net/InfoCenter/index?page=content&id=JSA11265&cat=SIRT_1&actp=LIST

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Q & A

Can this vulnerability be exploited remotely?

Yes. This vulnerability can be exploited by a remote non-authenticated attacker via the Internet.

Is there known malware, which exploits this vulnerability?

No. We are not aware of malware exploiting this vulnerability.