CVE-2021-46387

Name: CVE-2021-46387
Creator: NVD / NIST
Published: 2022-03-01T15:15:07.887+00:00
License: https://creativecommons.org/publicdomain/zero/1.0/

MEDIUMCVSS 6.1/10EPSS 21.03%

Last modified Jun 17, 2026

CVE-2021-46387 is a medium-severity vulnerability rated 6.1/10 on the CVSS scale. ZyXEL ZyWALL 2 Plus Internet Security Appliance is affected by Cross Site Scripting (XSS). Insecure URI handling leads to bypass security restriction to achieve Cross Site Scripting, which allows an attacker able to execute arbitrary JavaScript codes to perform multiple attacks such as clipboard hijacking and session hijacking.. EPSS estimates a 21.03% chance of exploitation in the next 30 days.

Description

ZyXEL ZyWALL 2 Plus Internet Security Appliance is affected by Cross Site Scripting (XSS). Insecure URI handling leads to bypass security restriction to achieve Cross Site Scripting, which allows an attacker able to execute arbitrary JavaScript codes to perform multiple attacks such as clipboard hijacking and session hijacking.

Metrics

CVSS 3.1

6.1/10

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

EPSS Probability

21.03%

97.3th percentile

Probability of exploitation in the next 30 days. Learn more

Weakness Enumeration

CWE-79

Affected Software

Vendor	Product	Versions
Zyxel	Zywall 2 Plus Internet Security Appliance Firmware	All versions

References

http://packetstormsecurity.com/files/166189/Zyxel-ZyWALL-2-Plus-Cross-Site-Scripting.htmlExploit, Third Party Advisory, VDB Entry
https://drive.google.com/drive/folders/1_XfWBLqxT2Mqt7uB663Sjlc62pE8-rcN?usp=sharingExploit, Third Party Advisory
https://www.zyxel.com/uk/en/products_services/zywall_2_plus.shtmlBroken Link, Vendor Advisory
https://www.zyxel.com/us/en/support/security_advisories.shtmlVendor Advisory
http://packetstormsecurity.com/files/166189/Zyxel-ZyWALL-2-Plus-Cross-Site-Scripting.htmlExploit, Third Party Advisory, VDB Entry
https://drive.google.com/drive/folders/1_XfWBLqxT2Mqt7uB663Sjlc62pE8-rcN?usp=sharingExploit, Third Party Advisory
https://www.zyxel.com/uk/en/products_services/zywall_2_plus.shtmlBroken Link, Vendor Advisory
https://www.zyxel.com/us/en/support/security_advisories.shtmlVendor Advisory

Timeline

Published: Mar 1, 2022
Last Modified: Jun 17, 2026
Status: Modified

Frequently Asked Questions

What is CVE-2021-46387?

How severe is CVE-2021-46387?

CVE-2021-46387 has a CVSS score of 6.1/10 (MEDIUM severity). The EPSS model estimates a 21.03% probability of exploitation in the next 30 days.

How do I fix CVE-2021-46387?

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-2021-46387?

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

Scan your code now

Source: NVD / NIST