"Attempting to drop privileges to root..." - Unable to login from WHM to cPanel

MaxTM

Registered
Apr 18, 2016
3
0
1
Ukaine
cPanel Access Level
Root Administrator
Hi, cPanel Team.

My problem was discussed before here. But there thread is died and no any answers with solution.

The problem in login from WHM to any user's cPanel account. When I click on cPanel icon in "List Accounts" page, new page opens but there goes next error:

_______________________________________________________
Internal Server Error
500

exit level [die] [pid=7313] (Attempting to drop privileges to root.)

cpsrvd/11.56.0.3 Server at my.server.net
_______________________________________________________

But, strange thing is: this error appear only in my Safari browser. :)
And another strange thing: this error not appears if I'm run new private windows in Safari.

This error not appear in Firefox in normal and private modes. In another browsers I didn't check.

The logs /usr/local/cpanel/logs/error_log:

[2016-04-18 17:10:58 +0100] die [cpsrvd] Attempting to drop privileges to root. at /usr/local/cpanel/Cpanel/AccessIds/ReducedPrivileges.pm line 141.
Cpanel::AccessIds::ReducedPrivileges::_prevent_dropping_to_root(0, 0) called at /usr/local/cpanel/Cpanel/AccessIds/ReducedPrivileges.pm line 77
Cpanel::AccessIds::ReducedPrivileges::call_as_user(CODE(0xf384d8), "root") called at /usr/local/cpanel/Cpanel/Server.pm line 1310
Cpanel::Server::update_lastlogin(Cpanel::Server=HASH(0x27e2e70), "root") called at /usr/local/cpanel/Cpanel/Server.pm line 1289
Cpanel::Server::newsession(Cpanel::Server=HASH(0x27e2e70), __CPANEL_HIDDEN__, 1, __CPANEL_HIDDEN__, __CPANEL_HIDDEN__, __CPANEL_HIDDEN__, __CPANEL_HIDDEN__, __CPANEL_HIDDEN__, __CPANEL_HIDDEN__, ...) called at cpsrvd.pl line 3803
cpanel::cpsrvd::handle_auth_transfer("") called at cpsrvd.pl line 1325
cpanel::cpsrvd::handle_one_connection() called at cpsrvd.pl line 784
cpanel::cpsrvd::script() called at cpsrvd.pl line 334
[2016-04-18 17:10:58 +0100] info [cpsrvd] Internal Server Error: "GET /xfercpanel HTTP/1.1" 500 exit level [die] [pid=7313] (Attempting to drop privileges to root.)


What I have tried to do to resolve this issue:

1. Tried to whole Safari clearing (cache, cookie, also removed all extensions).
2. Tried to different Easyapache configurations (with or without mod_security, mod_ruid2).
3. The certain option "Accounts that can access a cPanel user account" in "Tweak settings" set to "Root, Account-Owner, and cPanel User default"
4. Firewall CSF uninstalled.
5. ...

I know that the problem is in my WHM setup, because with the same Safari browser I try to login to user's cPanel accounts on another server and all fine. But, I can't resolve, which settings I made wrong. And no success with Google search...

Is anybody can help me?

I'm ready to provide any additional information.

Current used cPanel/WHM version: 56.0 build 3 - CURRENT branch
RELEASE branch also was tried.