CVE-2021-31373

Junos OS: SRX Series: Persistent XSS vulnerability in J-Web

Description

A persistent Cross-Site Scripting (XSS) vulnerability in Juniper Networks Junos OS on SRX Series, J-Web interface may allow a remote authenticated user to inject persistent and malicious scripts. An attacker can exploit this vulnerability to steal sensitive data and credentials from a web administration session, or hijack another user's active session to perform administrative actions. This issue affects: Juniper Networks Junos OS on SRX Series: 18.2 versions prior to 18.2R3-S8; 18.3 versions prior to 18.3R3-S5; 18.4 versions prior to 18.4R3-S8; 19.1 versions prior to 19.1R3-S5; 19.2 versions prior to 19.2R1-S7, 19.2R3-S3; 19.3 versions prior to 19.3R2-S6, 19.3R3-S3; 19.4 versions prior to 19.4R1-S4, 19.4R2-S4, 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 20.3R2-S1, 20.3R3.

Remediation

Solution:

  • The following software releases have been updated to resolve this specific issue: 18.2R3-S8, 18.3R3-S5, 18.4R3-S8, 19.1R3-S5, 19.2R1-S7, 19.2R3-S3, 19.3R2-S6, 19.3R3-S3, 19.4R1-S4, 19.4R2-S4, 19.4R3-S3, 20.1R2-S2, 20.1R3, 20.2R3-S1, 20.3R2-S1, 20.3R3, 20.4R1, and all subsequent releases.

Workaround:

  • To reduce the risk of exploitation of this issue, use access lists or firewall filters to limit access to only trusted administrative networks, hosts and users. Alternatively, J-Web can be disabled.

Categories

8.0
CVSS
Severity: High
CVSS 3.1 •
CVSS 2.0 •
EPSS 0.28%
Vendor Advisory juniper.net
Affected: Juniper Networks Junos OS
Published at:
Updated at:

References

Link Tags
https://kb.juniper.net/JSA11238 vendor advisory

Frequently Asked Questions

What is the severity of CVE-2021-31373?
CVE-2021-31373 has been scored as a high severity vulnerability.
How to fix CVE-2021-31373?
To fix CVE-2021-31373: The following software releases have been updated to resolve this specific issue: 18.2R3-S8, 18.3R3-S5, 18.4R3-S8, 19.1R3-S5, 19.2R1-S7, 19.2R3-S3, 19.3R2-S6, 19.3R3-S3, 19.4R1-S4, 19.4R2-S4, 19.4R3-S3, 20.1R2-S2, 20.1R3, 20.2R3-S1, 20.3R2-S1, 20.3R3, 20.4R1, and all subsequent releases.
Is CVE-2021-31373 being actively exploited in the wild?
As for now, there are no information to confirm that CVE-2021-31373 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-2021-31373?
CVE-2021-31373 affects Juniper Networks Junos OS.
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