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The KernelCare "Extra" Patchset for CentOS 6 & 7 with symlink protection is here

The KernelCare "Extra" Patchset for CentOS 6 & 7 with symlink protection is here

The KernelCare extra patchset includes all the security fixes from KernelCare for CentOS 6 and CentOS 7, as well as the symlink protection against a symlink race.

A symlink race attack is often used against shared hosting servers. It allows a malicious user to serve files that belong to other users by creating a symbolic link to those files. It is often used to access config.php files that belong to other users.

This extra patchset also includes the IPSet bugfix for CentOS 6.

We recommend you install this patchset for KernelCare running on CentOS 6 and CentOS 7. It is a requirement for Imunify360 for CentOS 6.

Note. For CloudLinux OS users this patch has already been compiled in the kernel.

The extra patchset is available in version 2.12-5 and newer. 

To enable extra patches and apply patch, run:

kcarectl --set-patch-type extra --update

To enable extra patches without update, run

kcarectl --set-patch-type extra

The ‘extra’ patch will be applied on the next automatic update.

To see details run:

kcarectl --patch-info

You should see something similar to:

OS: centos6
kernel: kernel-2.6.32-696.6.3.el6
time: 2017-07-31 22:46:22
uname: 2.6.32-696.6.3.el6

kpatch-name: 2.6.32/symlink-protection.patch
kpatch-description: symlink protection // If you see this patch, it means that you can enable symlink protection.
kpatch-kernel: kernel-2.6.32-279.2.1.el6
kpatch-cve: N/A
kpatch-cvss: N/A
kpatch-cve-url: N/A
kpatch-patch-url: https://gerrit.cloudlinux.com/#/c/16508/

kpatch-name: 2.6.32/symlink-protection.kpatch-1.patch
kpatch-description: symlink protection (kpatch adaptation)
kpatch-kernel: kernel-2.6.32-279.2.1.el6
kpatch-cve: N/A
kpatch-cvss: N/A
kpatch-cve-url: N/A
kpatch-patch-url: https://gerrit.cloudlinux.com/#/c/16508/

kpatch-name: 2.6.32/ipset-fix-list-shrinking.patch
kpatch-description: fix ipset list shrinking for no reason
kpatch-kernel: N/A
kpatch-cve: N/A
kpatch-cvss: N/A
kpatch-cve-url: N/A
kpatch-patch-url: https://bugs.centos.org/view.php?id=13499

To enable Symlink Owner Match Protection, add the following lines:

fs.enforce_symlinksifowner = 1
fs.symlinkown_gid = 48

Into /etc/sysconfig/kcare/sysctl.conf.

And run:

sysctl -w fs.enforce_symlinksifowner=1
sysctl -w fs.symlinkown_gid=48

Note: On standard RPM Apache installation, Apache is usually running under GID 48. On cPanel servers, Apache is running under user nobody, GID 99.

See http://docs.cloudlinux.com/index.html?symlink_owner_match_protection.html for details.

Click here to learn more about KernelCare.

Imunify360 2.5.0 beta is here, includes improved C...
mod_lsapi updated
 

Comments 17

Guest - Alejandro on Wednesday, 15 November 2017 14:21

Forget my last post, I have read again just to find

Note. For CloudLinux OS users this patch has already been compiled in the kernel.

Forget my last post, I have read again just to find Note. For CloudLinux OS users this patch has already been compiled in the kernel.
Guest - Samet Chan on Wednesday, 13 December 2017 16:57

Will you support for Debian and Plesk onyx for install this kernelcare?

Will you support for Debian and Plesk onyx for install this kernelcare?
Igor Seletskiy on Wednesday, 13 December 2017 17:03

Debian/Plesk should be supported with KC extension

Debian/Plesk should be supported with KC extension
Guest - Alessio on Tuesday, 30 January 2018 14:58

not working for me:

[email protected] [~]# kcarectl --set-patch-type extra --update
Unknown Kernel (CentOS Linux 3.10.0-693.17.1.el7.x86_64)
[email protected] [~]# kcarectl --patch-info
Unknown kernel (CentOS Linux 3.10.0-693.17.1.el7.x86_64), no patches available
[email protected] [~]# yum update kernelcare
Plugin abilitati:fastestmirror, priorities, tsflags, universal-hooks
EA4 | 3.0 kB 00:00:00
cpanel-addons-production-feed | 2.9 kB 00:00:00
cpanel-plugins | 2.9 kB 00:00:00
kernelcare | 2.6 kB 00:00:00
stable-arch | 951 B 00:00:00
stable-generic | 951 B 00:00:00
stable-noarch | 951 B 00:00:00
system-base | 3.6 kB 00:00:00
system-extras | 3.4 kB 00:00:00
system-updates-released | 3.4 kB 00:00:00
Loading mirror speeds from cached hostfile
* EA4: 208.100.0.204
* cpanel-addons-production-feed: 208.100.0.204
23 packages excluded due to repository priority protections
No packages marked for update

not working for me: [quote][email protected] [~]# kcarectl --set-patch-type extra --update Unknown Kernel (CentOS Linux 3.10.0-693.17.1.el7.x86_64) [email protected] [~]# kcarectl --patch-info Unknown kernel (CentOS Linux 3.10.0-693.17.1.el7.x86_64), no patches available [email protected] [~]# yum update kernelcare Plugin abilitati:fastestmirror, priorities, tsflags, universal-hooks EA4 | 3.0 kB 00:00:00 cpanel-addons-production-feed | 2.9 kB 00:00:00 cpanel-plugins | 2.9 kB 00:00:00 kernelcare | 2.6 kB 00:00:00 stable-arch | 951 B 00:00:00 stable-generic | 951 B 00:00:00 stable-noarch | 951 B 00:00:00 system-base | 3.6 kB 00:00:00 system-extras | 3.4 kB 00:00:00 system-updates-released | 3.4 kB 00:00:00 Loading mirror speeds from cached hostfile * EA4: 208.100.0.204 * cpanel-addons-production-feed: 208.100.0.204 23 packages excluded due to repository priority protections No packages marked for update [/quote]
Alexandre Parubochyi on Wednesday, 31 January 2018 13:03

This version is in the list of supported. Please, submit a ticket at https://cloudlinux.zendesk.com (KernelCare department) so our support team can help you with the issue.

This version is in the list of supported. Please, submit a ticket at https://cloudlinux.zendesk.com (KernelCare department) so our support team can help you with the issue.
Guest - kami on Monday, 11 June 2018 08:24

This is free for all. Or only for cloudlinux users?

This is free for all. Or only for cloudlinux users?
Alexandre Parubochyi on Monday, 11 June 2018 13:27

This is free and works only on CentOS 6 and 7

This is free and works only on CentOS 6 and 7
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