The Vigil@nce team watches public vulnerabilities impacting your computers, and then offers security solutions, a vigilance database and tools to fix them.

Vulnerability of Dovecot: denial de service via names mail header

Synthesis of the vulnerability 

An attacker can send a mail with a malicious "names" mail header in order to create a denial of service.
Vulnerable software: Debian, Fedora, Mandriva Linux, openSUSE, RHEL, SLES, Unix (platform) ~ not comprehensive.
Severity of this announce: 2/4.
Creation date: 27/05/2011.
Références of this computer vulnerability: CERTA-2011-AVI-316, CVE-2011-1929, DSA-2252-1, FEDORA-2011-7258, FEDORA-2011-7268, FEDORA-2011-7612, MDVSA-2011:101, openSUSE-SU-2011:0540-1, RHSA-2011:1187-01, SUSE-SR:2011:010, VIGILANCE-VUL-10687.

Description of the vulnerability 

The Dovecot program is an IMAP/POP3 server.

The file "lib-mail/message-header-parser.c" defines the functions performing the parsing mail headers.
A valid string ends with the guards "\ 0".

However when mail is received with the character "\ 0" contained in the header names, the parser does not correctly determine the size of the header, the pointer value line->name_len is too large and the pointer line->middle accesses a wrong memory area, causing a denial of service.

An attacker can therefore send a mail with a malicious "names" mail header in order to create a denial of service.
Full bulletin, software filtering, emails, fixes, ... (Request your free trial)

This cybersecurity announce impacts software or systems such as Debian, Fedora, Mandriva Linux, openSUSE, RHEL, SLES, Unix (platform) ~ not comprehensive.

Our Vigil@nce team determined that the severity of this threat alert is medium.

The trust level is of type confirmed by the editor, with an origin of internet client.

An attacker with a expert ability can exploit this computer weakness alert.

Solutions for this threat 

Docecot: version 2.0.13.
The version 2.0.13 is corrected:
  http://dovecot.org/releases/2.0/

Dovecot: version 1.2.17.
The version 1.2.17 is corrected:
  http://dovecot.org/releases/1.2/

Debian: new dovecot packages.
New packages are available:
  dovecot 1.2.15-7

Fedora: new dovecot packages.
New packages are available:
  dovecot-1.2.17-1.fc13
  dovecot-2.0.13-1.fc14
  dovecot-2.0.13-1.fc15

Mandriva: new dovecot packages.
New packages are available:
  dovecot-1.1.6-0.4mdv2009.0
  dovecot-1.2.15-0.2mdv2010.2
  dovecot-1.1.6-0.4mdvmes5.2

openSUSE: new dovecot packages.
New packages are available:
 - openSUSE 11.3 : dovecot12-1.2.17-2.2.1
 - openSUSE 11.4 : dovecot12-1.2.17-2.3.1

RHEL: new dovecot packages.
New packages are available:
  dovecot-0.99.11-10.EL4
  dovecot-1.0.7-7.el5_7.1
  dovecot-2.0.9-2.el6_1.1

SUSE: new packages (31/05/2011).
New packages are available, as indicated in information sources.
Full bulletin, software filtering, emails, fixes, ... (Request your free trial)

Computer vulnerabilities tracking service 

Vigil@nce provides an applications vulnerabilities alert. The Vigil@nce vulnerability database contains several thousand vulnerabilities.