Resteasy
CVE-2021-20293
MEDIUM
Vulnerability Assessment
| Weakness |
CWE
OWASP Top 10:2025
A05:2025 - Injection
ASVS 5.0
V1 - Encoding and Sanitization Output encoding, context-aware escaping
MITRE ATT&CK
2 techniques across 2 tactics: Initial Access, Execution The technique list with ATT&CK links and the kill-chain view is part of the Basic plan and up. |
| Impact | CVSS score of 6.1 (MEDIUM). Attack characteristics: network attack vector, low complexity, no privileges required, user interaction required. |
| Exploit ScenarioDerived | A remote attacker could inject malicious scripts into web pages viewed by other users by sending crafted requests to the affected application. No authentication is required to exploit this vulnerability. |
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Alert meAnalysisAI
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. Rated medium severity (CVSS 6.1), this vulnerability is remotely exploitable, no authentication required, low attack complexity. No vendor patch available.
RemediationAI
No vendor patch is available at time of analysis. Monitor vendor advisories for updates. Sanitize all user input, use Content-Security-Policy headers, encode output contextually (HTML, JS, URL). Use frameworks with built-in XSS protection.
Affected Packages
Source: OSV (Open Source Vulnerabilities)
Affects your stack
Affects 2 packages in maven
Checking this CVE against your own stacks and servers is part of the Basic plan and up.
Technical ContextAI · show details
This vulnerability is classified as Cross-Site Scripting (XSS) (CWE-79), which allows attackers to inject malicious scripts into web pages viewed by other users. 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. Affected products include: Redhat Resteasy, Netapp Oncommand Insight. Version information: up to 4.6.0..
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- Exploit and PoC references, threat intelligence from 22 sources
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Severity by source
AV:N/AC:L/PR:N/UI:R/S:C/C:L/I:L/A:N
Primary rating from NVD · only source for this CVE.
CVSS VectorNVD
DescriptionNVD
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.
Threat Intelligence Overview
NVD
CVE.org
EPSS
How this decision was reached
The engine reads each signal below and applies a fixed list of rules from top to bottom. The first rule that matches sets the recommended action – like a statement, every line is shown.
What every action level means
SSVC AssessmentENISA
Priority Score
Attack Technique
Cross-Site Scripting occurs when an application accepts untrusted data and sends it to a web browser without proper validation or encoding.
Affected Products (CPE)NVD
RESTEasy 2.3.1 before 2.3.8.SP2 and 3.x before 3.0.9, as used in Red Hat JBoss Enterprise Application Platform (EAP) 6.3
It was found that the fix for CVE-2016-9606 in versions 3.0.22 and 3.1.2 was incomplete and Yaml unmarshalling in Restea
RESTEasy enables GZIPInterceptor, which allows remote attackers to cause a denial of service via unspecified vectors. Ra
A flaw was found in all resteasy 3.x.x versions prior to 3.12.0.Final and all resteasy 4.x.x versions prior to 4.6.0.Fin
Cross-origin data exposure in RESTEasy's CorsFilter (CVSS 7.4) occurs when a deployment is configured with allowedOrigin
DocumentProvider in RESTEasy 2.3.7 and 3.0.9 does not configure the (1) external-general-entities or (2) external-parame
RESTEasy allows remote authenticated users to obtain sensitive information by leveraging "insufficient use of random val
JacksonJsonpInterceptor in RESTEasy might allow remote attackers to conduct a cross-site script inclusion (XSSI) attack.
Cross-site scripting (XSS) vulnerability in the default exception handler in RESTEasy allows remote attackers to inject
In RESTEasy the insecure File.createTempFile() is used in the DataSourceProvider, FileProvider and Mime4JWorkaround clas
A flaw was found in RESTEasy in all versions of RESTEasy up to 4.6.0.Final. Rated medium severity (CVSS 5.3), this vulne
A flaw was found in RESTEasy client in all versions of RESTEasy up to 4.5.6.Final. Rated medium severity (CVSS 5.3), thi
GitHub PoC
Exploit-DB