critical
9.3
CWE
863
Advisory Published
Updated

CVE-2022-22157: Junos OS: SRX Series: Traffic classification vulnerability when 'no-syn-check' is enabled

First published: Wed Jan 19 2022(Updated: )

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. 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. 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-S9, 18.4R3-S9; 19.1 versions prior to 19.1R2-S3, 19.1R3-S6; 19.2 versions prior to 19.2R1-S7, 19.2R3-S3; 19.3 versions prior to 19.3R2-S6, 19.3R3-S2; 19.4 versions prior to 19.4R2-S5, 19.4R3-S3; 20.1 versions prior to 20.1R2-S2, 20.1R3; 20.2 versions prior to 20.2R3-S1; 20.3 versions prior to 20.3R3; 20.4 versions prior to 20.4R2-S1, 20.4R3; 21.1 versions prior to 21.1R1-S1, 21.1R2. This issue does not affect Juniper Networks Junos OS versions prior to 18.4R1.

Credit: sirt@juniper.net

Affected SoftwareAffected VersionHow to fix
Junos OS Evolved=18.4
Junos OS Evolved=18.4-r1
Junos OS Evolved=18.4-r1-s1
Junos OS Evolved=18.4-r1-s2
Junos OS Evolved=18.4-r1-s3
Junos OS Evolved=18.4-r1-s4
Junos OS Evolved=18.4-r1-s5
Junos OS Evolved=18.4-r1-s6
Junos OS Evolved=18.4-r1-s7
Junos OS Evolved=18.4-r2
Junos OS Evolved=18.4-r2-s1
Junos OS Evolved=18.4-r2-s2
Junos OS Evolved=18.4-r2-s3
Junos OS Evolved=18.4-r2-s4
Junos OS Evolved=18.4-r2-s5
Junos OS Evolved=18.4-r2-s6
Junos OS Evolved=18.4-r2-s7
Junos OS Evolved=18.4-r2-s8
Junos OS Evolved=18.4-r3-s10
Junos OS Evolved=19.1
Junos OS Evolved=19.1-r1
Junos OS Evolved=19.1-r1-s1
Junos OS Evolved=19.1-r1-s2
Junos OS Evolved=19.1-r1-s3
Junos OS Evolved=19.1-r1-s4
Junos OS Evolved=19.1-r1-s5
Junos OS Evolved=19.1-r1-s6
Junos OS Evolved=19.1-r2
Junos OS Evolved=19.1-r2-s1
Junos OS Evolved=19.1-r2-s2
Junos OS Evolved=19.1-r3-s7
Junos OS Evolved=19.2
Junos OS Evolved=19.2-r1
Junos OS Evolved=19.2-r1-s1
Junos OS Evolved=19.2-r1-s2
Junos OS Evolved=19.2-r1-s3
Junos OS Evolved=19.2-r1-s4
Junos OS Evolved=19.2-r1-s5
Junos OS Evolved=19.2-r1-s6
Junos OS Evolved=19.2-r1-s7
Junos OS Evolved=19.2-r3-s4
Junos OS Evolved=19.3
Junos OS Evolved=19.3-r1
Junos OS Evolved=19.3-r1-s1
Junos OS Evolved=19.3-r2
Junos OS Evolved=19.3-r2-s1
Junos OS Evolved=19.3-r2-s2
Junos OS Evolved=19.3-r2-s3
Junos OS Evolved=19.3-r2-s4
Junos OS Evolved=19.3-r2-s5
Junos OS Evolved=19.3-r2-s6
Junos OS Evolved=19.3-r3-s4
Junos OS Evolved=19.4
Junos OS Evolved=19.4-r1
Junos OS Evolved=19.4-r1-s1
Junos OS Evolved=19.4-r1-s2
Junos OS Evolved=19.4-r1-s3
Junos OS Evolved=19.4-r1-s4
Junos OS Evolved=19.4-r2
Junos OS Evolved=19.4-r2-s1
Junos OS Evolved=19.4-r2-s2
Junos OS Evolved=19.4-r2-s3
Junos OS Evolved=19.4-r2-s4
Junos OS Evolved=19.4-r2-s5
Junos OS Evolved=19.4-r3
Junos OS Evolved=19.4-r3-s1
Junos OS Evolved=19.4-r3-s2
Junos OS Evolved=19.4-r3-s3
Junos OS Evolved=19.4-r3-s4
Junos OS Evolved=19.4-r3-s5
Junos OS Evolved=20.1
Junos OS Evolved=20.1-r1
Junos OS Evolved=20.1-r1-s1
Junos OS Evolved=20.1-r1-s2
Junos OS Evolved=20.1-r1-s3
Junos OS Evolved=20.1-r1-s4
Junos OS Evolved=20.1-r2
Junos OS Evolved=20.1-r2-s1
Junos OS Evolved=20.1-r2-s2
Junos OS Evolved=20.1-r3
Junos OS Evolved=20.1-r3-s1
Junos OS Evolved=20.1-r3-s2
Junos OS Evolved=20.2
Junos OS Evolved=20.2-r1
Junos OS Evolved=20.2-r1-s1
Junos OS Evolved=20.2-r1-s2
Junos OS Evolved=20.2-r1-s3
Junos OS Evolved=20.2-r2
Junos OS Evolved=20.2-r2-s1
Junos OS Evolved=20.2-r2-s2
Junos OS Evolved=20.2-r2-s3
Junos OS Evolved=20.2-r3
Junos OS Evolved=20.2-r3-s1
Junos OS Evolved=20.2-r3-s2
Junos OS Evolved=20.3
Junos OS Evolved=20.3-r1
Junos OS Evolved=20.3-r1-s1
Junos OS Evolved=20.3-r2
Junos OS Evolved=20.3-r2-s1
Junos OS Evolved=20.3-r3
Junos OS Evolved=20.4
Junos OS Evolved=20.4-r1
Junos OS Evolved=20.4-r1-s1
Junos OS Evolved=20.4-r2
Junos OS Evolved=20.4-r2-s1
Junos OS Evolved=20.4-r2-s2
Junos OS Evolved=21.1
Junos OS Evolved=21.1-r1
Junos OS Evolved=21.1-r1-s1
Junos OS Evolved=21.1-r2
Junos OS Evolved=21.1-r3
Junos OS Evolved=21.2
Junos OS Evolved=21.2-r1
Junos OS Evolved=21.2-r2

Remedy

The following software releases have been updated to resolve this specific issue: Junos OS 18.4R2-S9, 18.4R3-S9, 19.1R2-S3, 19.1R3-S6, 19.2R1-S7, 19.2R3-S3, 19.3R2-S6, 19.3R3-S2, 19.4R2-S5, 19.4R3-S3, 20.1R2-S2, 20.1R3, 20.2R3-S1, 20.3R3, 20.4R2-S1, 20.4R3, 21.1R1-S1, 21.1R2, 21.2R1, and all subsequent releases.

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Reference Links

Frequently Asked Questions

  • What is the vulnerability severity of CVE-2022-22157?

    The severity of CVE-2022-22157 is classified as high.

  • How can I fix CVE-2022-22157?

    To fix CVE-2022-22157, disable the 'no-syn-check' option in your device configuration.

  • Which devices are impacted by CVE-2022-22157?

    CVE-2022-22157 affects Juniper Networks Junos OS on SRX Series Services Gateways with specific versions.

  • What type of vulnerability is CVE-2022-22157?

    CVE-2022-22157 is a traffic classification vulnerability that allows bypassing Deep Packet Inspection rules.

  • What can an attacker achieve by exploiting CVE-2022-22157?

    Exploiting CVE-2022-22157 enables an attacker to access unauthorized networks or resources.

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