What’s Vulnerable › Vulnerabilities

CVE-2020-8823

• Severity: medium (CVSS 6.1 v3.1)
• Exploited in the wild: not listed in CISA KEV
• EPSS: 1.9% probability of exploitation in the next 30 days
• Public exploit or detection template: yes
• Published: 2020-02-10 · updated 2026-06-17
• Weakness: CWE-79

Description

htmlfile in lib/transport/htmlfile.js in SockJS before 0.3.0 is vulnerable to Reflected XSS via the /htmlfile c (aka callback) parameter.

Affected products

• sockjs: before 0.3.0 — fixed in 0.3.0

How to fix

Upgrade to a fixed version: sockjs 0.3.0. Check the vendor advisory for mitigations.

References

• https://github.com/theyiyibest/Reflected-XSS-on-SockJS
• https://github.com/theyiyibest/Reflected-XSS-on-SockJS/issues/1
• https://snyk.io/vuln/SNYK-JS-SOCKJS-548397
• https://www.sockjs.org
• https://github.com/theyiyibest/Reflected-XSS-on-SockJS
• https://github.com/theyiyibest/Reflected-XSS-on-SockJS/issues/1
• https://snyk.io/vuln/SNYK-JS-SOCKJS-548397
• https://www.sockjs.org

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