CVE-2021-20293
RESTEasy: PathParam in RESTEasy can lead to a reflected XSS attack
Severity
ModerateRed Hat Product Security
CVSS 3.1
Review impact separately from score.
Published · March 25, 2021
Updated · November 1, 2026
Description
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.
CVSS score applicability
The CVSS score(s) listed for this vulnerability do not reflect the associated product's status, and are included for informational purposes to better understand the severity of this vulnerability.
Mitigation
No mitigation is specified in collected source.
CVSS / CWE
CVSS 3.1 · 5.4CVSS:3.1/AV:N/AC:L/PR:N/UI:R/S:U/C:L/I:L/A:N
CWE-79 · Improper Neutralization of Input During Web Page Generation