Debian DSA-1852-1 : fetchmail - insufficient input validation

Medium Nessus Plugin ID 44717


The remote Debian host is missing a security-related update.


It was discovered that fetchmail, a full-featured remote mail retrieval and forwarding utility, is vulnerable to the 'Null Prefix Attacks Against SSL/TLS Certificates' recently published at the Blackhat conference. This allows an attacker to perform undetected man-in-the-middle attacks via a crafted ITU-T X.509 certificate with an injected null byte in the subjectAltName or Common Name fields.

Note, as a fetchmail user you should always use strict certificate validation through either these option combinations: sslcertck ssl sslproto ssl3 (for service on SSL-wrapped ports) or sslcertck sslproto tls1 (for STARTTLS-based services)


Upgrade the fetchmail packages.

For the oldstable distribution (etch), this problem has been fixed in version 6.3.6-1etch2.

For the stable distribution (lenny), this problem has been fixed in version 6.3.9~rc2-4+lenny1.

See Also

Plugin Details

Severity: Medium

ID: 44717

File Name: debian_DSA-1852.nasl

Version: 1.9

Type: local

Agent: unix

Published: 2010/02/24

Updated: 2019/08/02

Dependencies: 12634

Risk Information

Risk Factor: Medium

CVSS v2.0

Base Score: 6.4

Vector: CVSS2#AV:N/AC:L/Au:N/C:P/I:P/A:N

Vulnerability Information

CPE: p-cpe:/a:debian:debian_linux:fetchmail, cpe:/o:debian:debian_linux:4.0, cpe:/o:debian:debian_linux:5.0

Required KB Items: Host/local_checks_enabled, Host/Debian/release, Host/Debian/dpkg-l

Patch Publication Date: 2009/08/07

Reference Information

CVE: CVE-2009-2666

DSA: 1852

CWE: 310