A reflected Cross-Site Scripting (XSS) flaw was found in RESTEasy in all versions of RESTEasy up to 4.6.0.Final, where it did not properly handle URL encoding when calling @javax.ws.rs.PathParam without any @produces MediaType. This flaw allows an attacker to launch a reflected XSS attack. The highest threat from this vulnerability is to data confidentiality and integrity.

References

• https://nvd.nist.gov/vuln/detail/CVE-2021-20293
• https://bugzilla.redhat.com/show_bug.cgi?id=1942819
• https://security.netapp.com/advisory/ntap-20210727-0005/