Title

The AIX ldd command must be disabled. (Cat II impact)

Discussion

The ldd command provides a list of dependent libraries needed by a given binary, which is useful for troubleshooting software. Instead of parsing the binary file, some ldd implementations invoke the program with a special environment variable set, which causes the system dynamic linker to display the list of libraries. Specially crafted binaries can specify an alternate dynamic linker which may cause a program to be executed instead of examined. If the program is from an untrusted source, such as in a user home directory, or a file suspected of involvement in a system compromise, unauthorized software may be executed with the rights of the user running ldd.

Check Content

Consult vendor documentation concerning the "ldd" command. If the command provides protection from the execution of untrusted executables, this is not a finding. Determine the location of the system's "ldd" command: # find / -name ldd If no file exists, this is not a finding. Check the permissions of the found "ldd" file: # ls -lL <path to ldd> ---------- 1 bin bin 6289 Feb 28 2017 /usr/bin/ldd If the file mode of the file is more permissive than "0000", this is a finding

Fix Text

Disable the "ldd" command by removing its permissions using command: # chmod 0000 <path to ldd>

Additional Identifiers

Rule ID: SV-215329r991589_rule

Vulnerability ID: V-215329

Group Title: SRG-OS-000480-GPOS-00227

Expert Comments

CCIs tied to check.

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