wu-ftpd 2.6.1 allows remote attackers to execute arbitrary commands via a "~{" argument to commands such as CWD, which is not properly handled by the glob function (ftpglob).
https://exchange.xforce.ibmcloud.com/vulnerabilities/7611
http://www1.itrc.hp.com/service/cki/docDisplay.do?docId=HPSBUX0107-162
http://www.securityfocus.com/archive/82/180823
http://www.redhat.com/support/errata/RHSA-2001-157.html
http://www.novell.com/linux/security/advisories/2001_043_wuftpd_txt.html
http://www.linux-mandrake.com/en/security/2001/MDKSA-2001-090.php3
http://www.kb.cert.org/vuls/id/886083
http://www.debian.org/security/2001/dsa-087
http://www.cert.org/advisories/CA-2001-33.html
http://www.caldera.com/support/security/advisories/CSSA-2001-041.0.txt
http://marc.info/?l=bugtraq&m=100700363414799&w=2
http://download.immunix.org/ImmunixOS/7.0/updates/IMNX-2001-70-036-01
http://distro.conectiva.com.br/atualizacoes/?id=a&anuncio=000442