USN-56-1: exim4 vulnerabilities

Publication date

7 January 2005

Overview

exim4 vulnerabilities

Releases


Details

A flaw has been found in the host_aton() function, which can overflow
a buffer if it is presented with an illegal IPv6 address that has more
than 8 components. When supplying certain command line parameters, the
input was not checked, so that a local attacker could possibly exploit
the buffer overflow to run arbitrary code with the privileges of the
Exim mail server. (CAN-2005-0021)

Additionally, the BASE64 decoder in the SPA authentication handler did
not check the size of its output buffer. By sending an invalid BASE64
authentication string, a remote attacker could overflow the buffer,
which could possibly be exploited to run arbitrary code with the
privileges of the Exim mail server. (CAN-2005-0022)

A flaw has been found in the host_aton() function, which can overflow
a buffer if it is presented with an illegal IPv6 address that has more
than 8 components. When supplying certain command line parameters, the
input was not checked, so that a local attacker could possibly exploit
the buffer overflow to run arbitrary code with the privileges of the
Exim mail server. (CAN-2005-0021)

Additionally, the BASE64 decoder in the SPA authentication handler did
not check the size of its output buffer. By sending an invalid BASE64
authentication string, a remote attacker could overflow the buffer,
which could possibly be exploited to run arbitrary code with the
privileges of the Exim mail server. (CAN-2005-0022)

Update instructions

In general, a standard system update will make all the necessary changes.

Learn more about how to get the fixes.

The problem can be corrected by updating your system to the following package versions:

Ubuntu Release Package Version
4.10 warty exim4-daemon-heavy – 
exim4-daemon-light – 

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