The permission bits and user audit bits for HFS objects that are part of the FTP Server component will be properly configured.

Overview

Finding ID	Version	Rule ID	IA Controls	Severity
V-3239	IFTP0070	SV-3239r3_rule	DCCS-1 DCCS-2 DCSL-1	Medium

Description
HFS directories and files of the FTP Server provide the configuration and executable properties of this product. Failure to properly secure these objects may lead to unauthorized access resulting in the compromise of the integrity and availability of the operating system environment, ACP, and customer data.

STIG	Date
z/OS RACF STIG	2019-12-12

Details

Check Text ( C-41080r4_chk )

Refer to the following report produced by the UNIX System Services Data Collection: - USSCMDS.RPT(IFTP0070) Refer to the following report produced by the IBM Communications Server Data Collection: - PDI(IFTP0070) The HFS permission bits and user audit bits for each directory and file match or are more restrictive than the specified settings listed in the table. If the guidance is true, this is not a finding. FTP Server HFS Object Security Settings File Permission Bits User Audit Bits /usr/sbin/ftpd 1740 fff /usr/sbin/ftpdns 1755 fff /usr/sbin/tftpd 0644 faf /etc/ftp.data 0744 faf /etc/ftp.banner 0744 faf NOTES: Some of the files listed above are not used in every configuration. The absence of a file is not considered a finding. The /usr/sbin/ftpd and /usr/sbin/ftpdns objects are symbolic links to /usr/lpp/tcpip/sbin/ftpd and /usr/lpp/tcpip/sbin/ftpdns respectively. The permission and user audit bits on the targets of the symbolic links must have the required settings. The /etc/ftp.data file may not be the configuration file the server uses. It is necessary to check the SYSFTPD DD statement in the FTP started task JCL to determine the actual file. The TFTP Server does not perform any user identification or authentication, allowing any client to connect to the TFTP Server. Due to this lack of security, the TFTP Server will not be used. The TFTP Client is not secured from use. The permission bits for /usr/sbin/tftpd should be set to 644. The /etc/ftp.banner file may not be the banner file the server uses. It is necessary to check the BANNER statement in the FTP Data configuration file to determine the actual file. Also, the permission bit setting for this file must be set as indicated in the table above. A more restrictive set of permissions is not permitted. The following represents a hierarchy for permission bits from least restrictive to most restrictive: 7 rwx (least restrictive) 6 rw- 3 -wx 2 -w- 5 r-x 4 r-- 1 --x 0 --- (most restrictive) The possible audit bits settings are as follows: f log for failed access attempts a log for failed and successful access - no auditing

Fix Text (F-36626r1_fix)

The IAO with the assistance of a systems programmer with UID(0) and/or SUPERUSER access, will review the UNIX permission bits and user audit bits on the HFS directories and files for the FTP Server. Ensure they conform to the specifications in the table below: FTP Server HFS Object Security Settings File Permission Bits User Audit Bits /usr/sbin/ftpd 1740 fff /usr/sbin/ftpdns 1755 fff /usr/sbin/tftpd 0644 faf /etc/ftp.data 0744 faf /etc/ftp.banner 0744 faf The /usr/sbin/ftpd and /usr/sbin/ftpdns objects are symbolic links to /usr/lpp/tcpip/sbin/ftpd and /usr/lpp/tcpip/sbin/ftpdns respectively. The permission and user audit bits on the targets of the symbolic links must have the required settings. The TFTP Server does not perform any user identification or authentication, allowing any client to connect to the TFTP Server. Due to this lack of security, the TFTP Server will not be used. The TFTP Client is not secured from use. The /etc/ftp.data file may not be the configuration file the server uses. It is necessary to check the SYSFTPD DD statement in the FTP started task JCL to determine the actual file. The /etc/ftp.banner file may not be the banner file the server uses. It is necessary to check the BANNER statement in the FTP Data configuration file to determine the actual file. The following represents a hierarchy for permission bits from least restrictive to most restrictive: 7 rwx (least restrictive) 6 rw- 3 -wx 2 -w- 5 r-x 4 r-- 1 --x 0 --- (most restrictive) The possible audit bits settings are as follows: f log for failed access attempts a log for failed and successful access - no auditing Some of the files listed above (e.g., /etc/ftp.data) are not used in every configuration. While the absence of a file is generally not a security issue, the existence of a file that has not been properly secured can often be an issue. Therefore, all files that do exist should have the specified permission and audit bit settings. The following commands can be used (from a user account with an effective UID(0)) to update the permission bits and audit bits: chmod 1740 /usr/lpp/tcpip/sbin/ftpd chaudit rwx=f /usr/lpp/tcpip/sbin/ftpd chmod 1755 /usr/lpp/tcpip/sbin/ftpdns chaudit rwx=f /usr/lpp/tcpip/sbin/ftpdns chmod 0744 /etc/ftp.data chaudit w=sf,rx+f /etc/ftp.data chmod 0744 /etc/ftp.banner chaudit w=sf,rx+f /etc/ftp.banner