MIT Kerberos 5: Multiple vulnerabilities

Security Team Contact Address

Updated April 08, 2009

1. Gentoo Linux Security Advisory

Advisory Reference	GLSA 200904-09 / mit-krb5
Release Date	April 08, 2009
Latest Revision	April 08, 2009: 01
Impact	high
Exploitable	remote

Package	Vulnerable versions	Unaffected versions	Architecture(s)
app-crypt/mit-krb5	< 1.6.3-r6	>= 1.6.3-r6	All supported architectures

Related bugreports: #262736, #263398

Synopsis

Multiple vulnerabilites in MIT Kerberos 5 might allow remote unauthenticated users to execute arbitrary code with root privileges.

2. Impact Information

Background

MIT Kerberos 5 is a suite of applications that implement the Kerberos network protocol. kadmind is the MIT Kerberos 5 administration daemon, KDC is the Key Distribution Center.

Description

Multiple vulnerabilities have been reported in MIT Kerberos 5:

A free() call on an uninitialized pointer in the ASN.1 decoder when decoding an invalid encoding (CVE-2009-0846).
A buffer overread in the SPNEGO GSS-API application, reported by Apple Product Security (CVE-2009-0844).
A NULL pointer dereference in the SPNEGO GSS-API application, reported by Richard Evans (CVE-2009-0845).
An incorrect length check inside an ASN.1 decoder leading to spurious malloc() failures (CVE-2009-0847).

Impact

A remote unauthenticated attacker could exploit the first vulnerability to cause a Denial of Service or, in unlikely circumstances, execute arbitrary code on the host running krb5kdc or kadmind with root privileges and compromise the Kerberos key database. Exploitation of the other vulnerabilities might lead to a Denial of Service in kadmind, krb5kdc, or other daemons performing authorization against Kerberos that utilize GSS-API or an information disclosure.

3. Resolution Information

Workaround

There is no known workaround at this time.

Resolution

All MIT Kerberos 5 users should upgrade to the latest version:

Code Listing 3.1: Resolution

# emerge --sync
# emerge --ask --oneshot --verbose ">=app-crypt/mit-krb5-1.6.3-r6"

4. References