Vulnerability Note VU#720017

Entrust Authority Security Manager (EASM) does not enforce multiple authorization requirement for master user password change

Original Release date: 04 Apr 2003 | Last revised: 27 Jun 2003

Overview

Entrust Authority Security Manager contains a vulnerability that could allow a master user to change the password of another master user. A master user could exploit this vulnerability to perform operations that otherwise require authorization by multiple master users.

Description

Entrust Authority Security Manager (EASM) is a public-key infrastructure (PKI) that includes a certificate authority (CA). EASM defines several privileged master users that have the ability to perform sensitive master user functions on the CA. Sensitive master user functions can be configured to require multiple authorizations by master users.

Changing the password of a master user is considered to be a sensitive operation that requires multiple authorizations. Under certain conditions, possibly involving the command line interface (CLI), the multiple authorization requirement is not enforced, allowing a single master user to change the password of another master user.

The following text was provided by Keith Sollers of Ernst & Young:

    ===============================================================================

    Entrust Authority Security Manager Multiple Authorization Vulnerability

    Ernst & Young announces the discovery of a vulnerability in Entrust
    Authority Security Manager (EASM) for Solaris and Windows NT.

    The Common Vulnerabilities and Exposures (CVE) project has assigned
    the name CAN-2002-0712 to this issue. This is a candidate for inclusion
    in the CVE list (
    http://cve.mitre.org), which standardizes names for
    security problems.

    Background:

    EASM functions as a certificate authority within a public-key
    infrastructure (PKI).  It issues certificates for entities and publishes
    certificate status information to an associated repository.  Special
    users, called master users, are responsible for maintenance of critical
    processes that enable EASM to perform its core functions.  By default,
    three master user IDs are created upon installation of EASM, master1,
    master2, and master3.  These user IDs cannot be changed.

    EASM can be configured to require multiple authorization for so-called
    sensitive master user functions.  However, the master user function of
    changing another master user's password is not a sensitive function.
    Therefore, any one master user can circumvent the multiple authorization
    requirement for any sensitive function by first changing another master
    user's password to a known password, and then impersonating that other
    master user during the multiple authorization process.

    Systems Affected:

    Solaris 7 and Windows NT 4.0 with EASM version 6.0 installed.  EASM
    version 6.0 on other platforms, and previous versions of EASM on all
    platforms, may also be affected, but were not tested.

    Impact:

    For systems that utilize the EASM multiple authorization feature for
    master user sensitive functions, a single attacker would be successful
    in performing unauthorized functions on the EASM, such as stopping critical
    services (denial of service).

    Recommendation:

    For systems where the multiple authorization of master user sensitive
    functions is desired, we recommend the introduction of mitigating logical
    and/or physical controls that assure multiple master users are involved
    during the multiple authorization process.

    THE INFORMATION IN THIS VULNERABILITY ALERT IS PROVIDED BY ERNST & YOUNG LLP
    "AS IS", "WHERE IS", WITH NO WARRANTY OF ANY KIND, AND ERNST & YOUNG LLP HEREBY
    DISCLAIMS THE IMPLIED WARRANTIES OF NON-INFRINGEMENT, MERCHANTABILITY AND
    FITNESS FOR A PARTICULAR PURPOSE.  ERNST & YOUNG LLP SHALL HAVE NO LIABILITY
    FOR ANY DAMAGE, CLAIM OR LOSS RESULTING FROM YOUR USE OF THE INFORMATION
    CONTAINED IN THIS VULNERABILITY ALERT.


    ===============================================================================

Impact

A single EASM master user could change the password of another master user, thereby gaining the ability perform sensitive operations that require multiple authorizations. This could allow a master user to stop EASM services, causing a denial of service.

Solution

Upgrade or Patch
This issue is resolved with mandatory upgrade 6.0.1 released on July 2, 2002.


Provide Physical Access Controls

Provide additional logical and/or physical access controls to enforce the multiple authorization requirement to change master users' passwords.

Systems Affected (Learn More)

VendorStatusDate NotifiedDate Updated
EntrustAffected12 Feb 200303 Apr 2003
If you are a vendor and your product is affected, let us know.

CVSS Metrics (Learn More)

Group Score Vector
Base N/A N/A
Temporal N/A N/A
Environmental N/A N/A

References

Credit

This vulnerability was analyzed and reported by Keith Sollers of Ernst and Young.

This document was written by Art Manion.

Other Information

  • CVE IDs: CAN-2002-0712
  • Date Public: 04 Apr 2003
  • Date First Published: 04 Apr 2003
  • Date Last Updated: 27 Jun 2003
  • Severity Metric: 0.15
  • Document Revision: 30

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