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  1. OFBiz
  2. OFBIZ-1525 Issue to group security concerns
  3. OFBIZ-11407

Upgrade Tomcat from 9.0.29 to 9.0.31 (CVE-2020-1938)

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    Details

    • Type: Sub-task
    • Status: Closed
    • Priority: Major
    • Resolution: Implemented
    • Affects Version/s: Trunk
    • Fix Version/s: Upcoming Branch
    • Component/s: framework
    • Labels:
      None
    • Sprint:
      Bug Crush Event - 21/2/2015

      Description

      CVE-2020-1938 AJP Request Injection and potential Remote Code Execution

      Severity: High

      Vendor: The Apache Software Foundation

      Versions Affected:
      Apache Tomcat 9.0.0.M1 to 9.0.30
      Apache Tomcat 8.5.0 to 8.5.50
      Apache Tomcat 7.0.0 to 7.0.99

      Description:
      When using the Apache JServ Protocol (AJP), care must be taken when
      trusting incoming connections to Apache Tomcat. Tomcat treats AJP
      connections as having higher trust than, for example, a similar HTTP
      connection. If such connections are available to an attacker, they can
      be exploited in ways that may be surprising.

      Prior to Tomcat 9.0.31, 8.5.51 and 7.0.100, Tomcat shipped with an AJP
      Connector enabled by default that listened on all configured IP
      addresses. It was expected (and recommended in the security guide) that
      this Connector would be disabled if not required.

      Prior to this vulnerability report, the known risks of an attacker being
      able to access the AJP port directly were:

      • bypassing security checks based on client IP address
      • bypassing user authentication if Tomcat was configured to trust
        authentication data provided by the reverse proxy
        This vulnerability report identified a mechanism that allowed the following:
      • returning arbitrary files from anywhere in the web application
        including under the WEB-INF and META-INF directories or any other
        location reachable via ServletContext.getResourceAsStream()
      • processing any file in the web application as a JSP
        Further, if the web application allowed file upload and stored those
        files within the web application (or the attacker was able to control
        the content of the web application by some other means) then this, along
        with the ability to process a file as a JSP, made remote code execution
        possible.

      Mitigation:
      It is important to note that mitigation is only required if an AJP port
      is accessible to untrusted users.

      • If AJP support is not required, the Connector may be disabled e.g. by
        removing the AJP Connector element from the server.xml file
      • If AJP support is required, untrusted users may be prevented from
        accessing the AJP port by one or more of the following means:
      • configuring appropriate network firewall rules
      • configuring an explicit address attribute to the connector so that
        the Connector listens on a non-public interface
      • configuring a shared secret for the AJP connection
        Users wishing to take a defence-in-depth approach and block the vector
        that permits returning arbitrary files and execution as JSP may upgrade to:
      • Apache Tomcat 9.0.31 or later
      • Apache Tomcat 8.5.51 or later
      • Apache Tomcat 7.0.100 or later
        Users should note that a number of changes were made to the default AJP
        Connector configuration in these versions to harden the default
        configuration. The changes are:
      • The AJP Connector is commented out in the provided server.xml file.
      • The "requiredSecret" attribute has been renamed "secret" (the old name
        continues to work but is deprecated).
      • A new attribute "secretRequired" has been added which defaults to
        "true". When this attribute is "true", the AJP Connector will not
        start unless a shared secret has been configured.
      • The default listen address for the AJP Connector is now the loopback
        address.
        It is likely that users upgrading to 9.0.31, 8.5.51 or 7.0.100 and later
        will need to make small changes to their configurations as a result.

      References:
      [1] http://tomcat.apache.org/security-9.html
      [2] http://tomcat.apache.org/security-8.html
      [3] http://tomcat.apache.org/securit

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              • Assignee:
                mbrohl Michael Brohl
                Reporter:
                mbrohl Michael Brohl
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                • Created:
                  Updated:
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