pam_ldap and nss_ldap: Plain text authentication leak

pam_ldap and nss_ldap: Plain text authentication leak pam_ldap and nss_ldap fail to restart TLS when following a referral, possibly leading to credentials being sent in plain text. pam_ldap nss_ldap July 14, 2005 July 14, 2005: 01 96767 remote 239-r1 226-r1 239-r1 178-r1 178-r1

pam_ldap is a Pluggable Authentication Module which allows authentication against an LDAP directory. nss_ldap is a Name Service Switch module which allows 'passwd', 'group' and 'host' database information to be pulled from LDAP. TLS is Transport Layer Security, a protocol that allows encryption of network communications.

Rob Holland of the Gentoo Security Audit Team discovered that pam_ldap and nss_ldap fail to use TLS for referred connections if they are referred to a master after connecting to a slave, regardless of the "ssl start_tls" ldap.conf setting.

An attacker could sniff passwords or other sensitive information as the communication is not encrypted.

pam_ldap and nss_ldap can be set to force the use of SSL instead of TLS.

All pam_ldap users should upgrade to the latest version:


    # emerge --sync
    # emerge --ask --oneshot --verbose ">=sys-auth/pam_ldap-178-r1"

All nss_ldap users should upgrade to the latest version:


    # emerge --sync
    # emerge --ask --oneshot --verbose sys-auth/nss_ldap

CAN-2005-2069 tigger tigger koon