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Vulnerability axent Affected Axent 5.0 for Unix Description This information was forwarded to Security Focus. Certain checks within Axent's ESM 5.0 for Unix may prevent legitimate users from logging on to scanned hosts. Specifically, four checks within the security auditing program may cause this denial of service: * Check PATH using 'su' * Check PATH by modifying startup script * Check umask using 'su' * Check umask by modifying startup script These checks are not enabled in the default policy templates. When ESM is checking PATH (or umask) values, it will 'su' to the user's account. If the user's script calls a menu function, ESM will not respond and the check will hang. To overcome this problem, ESM copies the startup script to the /tmp directory, adds additional values to the end of the script, and copies the script back to the user's directory. The new values in the script will echo the PATH and umask values to a file called .esmvalues in the user's home directory the next time the user logs in. When ESM is run again, it will read the contents of .esmvalues to determine the PATH and umask values. This procedure eliminates the problems associated with 'su'ing to the account and hanging on a menu call. Unfortunately, when ESM copies the file to /tmp, file ownership and permissions are changed to 'root'. When the file is copied back to the user's directory, only root has access - legitimate users will not be able to execute their login script. Solution This bug should be fixed in the upcoming 5.0.1 release. The first statement indicates that users cannot log into scanned hosts. This is not true--users can log in, but they will not be able to access their startup scripts. This bug constitutes more of an inconvenience to the user, than a security threat. The bug was discovered a short time ago and there is a current procedure for correcting the ownership of files that may have been affected. Currently there is a newer version of the affected usrfiles module that does not change the ownership of the startup scripts. This procedure and/or the updated module can be obtained by contacting AXENT support. This version of the usrfiles module is also included in the August HotFix for ESM that customers can remotely install on all systems. The hot fix is only needed for ESM 5.0 UNIX agents. Earlier versions of ESM agents do not have this problem. The fix will also be included in the upcoming ESM 5.0.1 release. As was indicated above, this check was not turned on by default and most ESM 5.0 customers have probably not used it. If you desire the procedure to correct the affected files or the updated module, please contact AXENT support.