CVE-2022-22157

Name: CVE-2022-22157
Creator: NVD / NIST
Published: 2022-01-19T01:15:08.45+00:00
License: https://creativecommons.org/publicdomain/zero/1.0/

CRITICALCVSS 9.3/10EPSS 0.66%

Last modified Jun 17, 2026

CVE-2022-22157 is a critical-severity vulnerability rated 9.3/10 on the CVSS scale. 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. EPSS estimates a 0.66% chance of exploitation in the next 30 days.

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. 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.

Metrics

CVSS 3.1

9.3/10

CVSS:3.1/AV:N/AC:L/PR:N/UI:N/S:C/C:H/I:L/A:N

EPSS Probability

0.66%

46.8th percentile

Probability of exploitation in the next 30 days. Learn more

Weakness Enumeration

Affected Software

Vendor	Product	Versions
Juniper	Junos	18.4
Juniper	Junos	19.1
Juniper	Junos	19.2
Juniper	Junos	19.3
Juniper	Junos	19.4
Juniper	Junos	20.1
Juniper	Junos	20.2
Juniper	Junos	20.3
Juniper	Junos	20.4
Juniper	Junos	21.1
Juniper	Junos	21.2

References

https://kb.juniper.net/JSA11265Vendor Advisory
https://kb.juniper.net/JSA11265Vendor Advisory

Timeline

Published: Jan 19, 2022
Last Modified: Jun 17, 2026
Status: Modified

Frequently Asked Questions

What is CVE-2022-22157?

How severe is CVE-2022-22157?

CVE-2022-22157 has a CVSS score of 9.3/10 (CRITICAL severity). The EPSS model estimates a 0.66% probability of exploitation in the next 30 days.

How do I fix CVE-2022-22157?

Check the vendor references and advisories linked above for patched versions and mitigation guidance. You can also run a Strix scan to test if your systems are affected.

Are you affected by CVE-2022-22157?

Run a free Strix scan to check your systems for this vulnerability.

Scan your code now

Source: NVD / NIST