Gentoo Logo

Fetchmail: Denial of Service and password disclosure


1.  Gentoo Linux Security Advisory

Version Information

Advisory Reference GLSA 200701-13 / fetchmail
Release Date January 22, 2007
Latest Revision January 22, 2007: 01
Impact normal
Exploitable remote
Package Vulnerable versions Unaffected versions Architecture(s)
net-mail/fetchmail < 6.3.6 >= 6.3.6 All supported architectures

Related bugreports: #160463


Fetchmail has been found to have numerous vulnerabilities allowing for Denial of Service and password disclosure.

2.  Impact Information


Fetchmail is a remote mail retrieval and forwarding utility.


Neil Hoggarth has discovered that when delivering messages to a message delivery agent by means of the "mda" option, Fetchmail passes a NULL pointer to the ferror() and fflush() functions when refusing a message. Isaac Wilcox has discovered numerous means of plain-text password disclosure due to errors in secure connection establishment.


An attacker could deliver a message via Fetchmail to a message delivery agent configured to refuse the message, and crash the Fetchmail process. SMTP and LMTP delivery modes are not affected by this vulnerability. An attacker could also perform a Man-in-the-Middle attack, and obtain plain-text authentication credentials of users connecting to a Fetchmail process.

3.  Resolution Information


There is no known workaround at this time.


All fetchmail users should upgrade to the latest version:

Code Listing 3.1: Resolution

# emerge --sync
# emerge --ask --oneshot --verbose ">=net-mail/fetchmail-6.3.6"

4.  References


Page updated January 22, 2007

Summary: This is a Gentoo Linux Security Advisory

Security Team
Contact Address

Donate to support our development efforts.

Copyright 2001-2015 Gentoo Foundation, Inc. Questions, Comments? Contact us.