Improper Neutralization of Input During Web Page Generation ('Cross-site Scripting')
Some enterprises require that REST API endpoints include security-related headers in REST responses. Headers such as X-Frame-Options and X-Content-Type-Options are generally advisable, however some information security professionals additionally look for X-Permitted-Cross-Domain-Policies and X-XSS-Protection, which are more generally applicable to HTML endpoint, to be included too. These headers were not included in Couchbase Server 5.5.0 and 5.1.2 . They are now included in version 6.0.2 in responses from the Couchbase Server Views REST API (port 8092).
CWE-79 - Cross Site Scripting
Cross-Site Scripting, commonly referred to as XSS, is the most dominant class of vulnerabilities. It allows an attacker to inject malicious code into a pregnable web application and victimize its users. The exploitation of such a weakness can cause severe issues such as account takeover, and sensitive data exfiltration. Because of the prevalence of XSS vulnerabilities and their high rate of exploitation, it has remained in the OWASP top 10 vulnerabilities for years.