6.1 Medium
CVSS3
Attack Vector
NETWORK
Attack Complexity
LOW
Privileges Required
NONE
User Interaction
REQUIRED
Scope
CHANGED
Confidentiality Impact
LOW
Integrity Impact
LOW
Availability Impact
NONE
CVSS:3.1/AV:N/AC:L/PR:N/UI:R/S:C/C:L/I:L/A:N
0.001 Low
EPSS
Percentile
38.7%
JStachio fails to escape single quotes '
in HTML, allowing an attacker to inject malicious code.
Use the following template code:
<div></div>
Set the value variable to ' onblur='alert(1)
.
public class Escaping {
public static void main(String[] args) {
Model model = new Model("' onblur='alert(1)");
String result = AttributeTemplate.of().execute(model);
System.out.println(result);
}
@JStache(template = "<div></div>",
name="AttributeTemplate")
@JStacheConfig(contentType= Html.class)
public static class Model {
public final String value;
public Model(String value) {
this.value = value;
}
public String getValue() {
return value;
}
}
}
Expected Result:
The resulting output should have properly escaped the single quotes and not execute the injected JavaScript code.
Actual Result:
The resulting output is vulnerable and renders as follows:
<div></div>
This vulnerability can be exploited by an attacker to execute arbitrary JavaScript code in the context of other users visiting pages that use this template engine. This can lead to various consequences, including session hijacking, defacement of web pages, theft of sensitive information, or even the propagation of malware.
To mitigate this vulnerability, the template engine should properly escape special characters, including single quotes. Common practice is to escape '
as '
.
As long as users stick with double quotes "
for HTML attributes, they should not be affected.
For instance, Rocker’s general purpose HTML escaping
CPE | Name | Operator | Version |
---|---|---|---|
io.jstach:jstachio | lt | 1.0.1 |
github.com/advisories/GHSA-gwxv-jv83-6qjr
github.com/jstachio/jstachio/commit/7b2f78377d1284df14c580be762a25af5f8dcd66
github.com/jstachio/jstachio/issues/157
github.com/jstachio/jstachio/pull/158
github.com/jstachio/jstachio/releases/tag/v1.0.1
github.com/jstachio/jstachio/security/advisories/GHSA-gwxv-jv83-6qjr
nvd.nist.gov/vuln/detail/CVE-2023-33962