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FreeBSD Ports Security Advisory: FreeBSD-SA-00:28.majordomo

Jul 06, 2000, 19:21 (0 Talkback[s])


Desktop-as-a-Service Designed for Any Cloud ? Nutanix Frame

Date: Wed, 5 Jul 2000 16:08:22 -0700
From: FreeBSD Security Advisories security-advisories@freebsd.org
Subject: FreeBSD Ports Security Advisory: FreeBSD-SA-00:28.majordomo


FreeBSD-SA-00:28                                           Security Advisory
                                                                FreeBSD, Inc.

Topic:          majordomo is not safe to run on multi-user machines

Category:       ports
Module:         majordomo
Announced:      2000-07-05
Affects:        Ports collection.
Corrected:      See below
Vendor status:  Problem documented
FreeBSD only:   NO
I. Background

Majordomo is a popular mailing-list manager.

II. Problem Description

Majordomo contains a number of perl scripts which are executed by a setuid wrapper for providing mailing-list management functionality. However there are numerous weaknesses in these scripts which allow unprivileged users to run arbitrary commands as the majordomo user, as well as obtaining read and write access to the mailing list data.

The majordomo port is not installed by default, nor is it "part of FreeBSD" as such: it is part of the FreeBSD ports collection, which contains over 3400 third-party applications in a ready-to-install format.

FreeBSD makes no claim about the security of these third-party applications, although an effort is underway to provide a security audit of the most security-critical ports.

III. Impact

Unprivileged local users can run commands as the 'majordomo' user, including accessing and modifying mailing-list subscription data.

If you have not chosen to install the majordomo port/package, then your system is not vulnerable to this problem.

IV. Workaround

Deinstall the majordomo port/package, if you you have installed it, or limit the permissions of the majordomo/ directory and/or its contents appropriately (see below).

V. Solution

Since the vendor has chosen not to fix the various security holes in the default installation of majordomo, there is no simple solution. It may be possible to adequately secure the majordomo installation while retaining required functionality, by tightening the permissions on the /usr/local/majordomo directory and/or its contents, but these actions are not taken by the FreeBSD port and are beyond the scope of this advisory.

Instead we recommend that majordomo not be used on a system which contains untrusted users, or an alternative mailing-list manager be used. There are several such utilities in the FreeBSD ports collection.

Version: 2.6.2