[SECURITY-L] CAIS-Alerta: Vulnerabilidade remota no servidor FTP ProFTPD

Ter Set 23 15:31:51 -03 2003

----- Forwarded message from Centro de Atendimento a Incidentes de Seguranca <cais em cais.rnp.br> -----

From: Centro de Atendimento a Incidentes de Seguranca <cais em cais.rnp.br>
Subject: CAIS-Alerta: Vulnerabilidade remota no servidor FTP ProFTPD
To: rnp-alerta em cais.rnp.br, rnp-seg em cais.rnp.br
Date: Tue, 23 Sep 2003 15:18:18 -0300 (BRT)

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Prezados,

O CAIS esta' repassando o alerta da ISS X-Force, ISS Security Brief:
"ProFTPD ASCII File Remote Compromise Vulnerability", que trata de uma
vulnerabilidade existente no servidor ProFTPD que ocorre devido a um erro
no gerenciamento de upload de arquivos em formato ASCII, que pode permitir
a um atacante remoto executar codigo arbitrario.

Um atacante, capaz de enviar um arquivo no formato ASCII para o servidor,
pode causar um buffer overflow, resultando na execucao remota de codigo
com os privilegios do usuario que executa o servidor ftp, normalmente
"root". O ataque somente sera' realizado com sucesso se o usuario possuir
permissoes para enviar arquivos para o servidor.

Sistemas afetados:

	. ProFTPD 1.2.7
	. ProFTPD 1.2.8
	. ProFTPD 1.2.8rc1
	. ProFTPD 1.2.8rc2
	. ProFTPD 1.2.9rc1
	. ProFTPD 1.2.9rc2

E' possivel que versoes anteriores a 1.2.7 tambem sejam vulneraveis ao
ataque.

Correcoes disponiveis:

Recomenda-se fazer a atualizacao para as versoes disponiveis em
ftp.proftpd.org:

. ftp://ftp.proftpd.org/distrib/source/proftpd-1.2.7p.tar.gz
. ftp://ftp.proftpd.org/distrib/source/proftpd-1.2.8p.tar.gz
. ftp://ftp.proftpd.org/distrib/source/proftpd-1.2.9rc1p.tar.gz
. ftp://ftp.proftpd.org/distrib/source/proftpd-1.2.9rc2p.tar.gz

Maiores informacoes:

	. http://xforce.iss.net/xforce/alerts/id/154
	. http://www.proftpd.org/

O CAIS recomenda aos administradores manterem seus sistemas e aplicativos
sempre atualizados, de acordo com as ultimas versoes e correcoes
disponibilizadas pelos fabricantes.

Atenciosamente,

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Internet Security Systems Security Brief
September 23, 2003

ProFTPD ASCII File Remote Compromise Vulnerability

Synopsis:

ISS X-Force has discovered a flaw in the ProFTPD Unix FTP server. ProFTPD
is a highly configurable FTP (File Transfer Protocol) server for Unix
that allows for per-directory access restrictions, easy configuration of
virtual FTP servers, and support for multiple authentication mechanisms.
A flaw exists in the ProFTPD component that handles incoming ASCII file
transfers.

Impact:

An attacker capable of uploading files to the vulnerable system can
trigger a buffer overflow and execute arbitrary code to gain complete
control of the system. Attackers may use this vulnerability to destroy,
steal, or manipulate data on vulnerable FTP sites.

Affected Versions:

ProFTPD 1.2.7
ProFTPD 1.2.8
ProFTPD 1.2.8rc1
ProFTPD 1.2.8rc2
ProFTPD 1.2.9rc1
ProFTPD 1.2.9rc2

Note: Versions previous to version 1.2.7 may also be vulnerable.

For the complete ISS X-Force Security Advisory, please visit:
http://xforce.iss.net/xforce/alerts/id/154

______

About Internet Security Systems (ISS)
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online resources from an ever-changing spectrum of threats and misuse.
Internet Security Systems is headquartered in Atlanta, GA, with
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