CVE-2004-2771

The expand function in fio.c in Heirloom mailx 12.5 and earlier and BSD mailx 8.1.2 and earlier allows remote attackers to execute arbitrary commands via shell metacharacters in an email address.

What this means for your business

It affects Oracle Linux. It matters if your company, or a supplier that handles your data, runs it.
Code showing how to exploit it has been published, but real attacks have not been confirmed.
An attacker can use it remotely, over a network.
FIRST's prediction model gives it a 7% chance of attack attempts being seen in the next 30 days, ranking above 93% of all known flaws.

What to do

1Check whether your company or your suppliers run Oracle Linux, and which version. The affected versions are listed further down this page.
2If you do, follow the vendor's guidance. No patch reference has been published yet.

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Scoring

CVSS: 7.5 (v2.0)
Vector: AV:N/AC:L/Au:N/C:P/I:P/A:P
Weakness: CWE-20
Assigned by: secalert@redhat.com

Dates

Published: 2014-12-24
Last modified: 2026-09-23
Sources: NVD

Affected products

Oracle Linux6, 7
Redhat Enterprise Linux6.0, 7.0
Bsd Mailx Project Bsd Mailx- 8.1.2
Heirloom Mailx- 12.5

As listed in the NVD configuration data. Not a statement about your estate.