Important kernel security update: CVE-2018-13405 and other; Virtuozzo ReadyKernel patch 55.0 for all supported Virtuozzo 7.0 kernels¶
Issue date: 2018-08-02
Applies to: Virtuozzo 7.0
Virtuozzo Advisory ID: VZA-2018-049
1. Overview¶
The cumulative Virtuozzo ReadyKernel patch was updated with security and stability fixes. The patch applies to all supported Virtuozzo 7.0 kernels.
2. Security Fixes¶
[Important] It was discovered that the local users could create files with an unintended group ownership and with group execution and SGID permission bits set. It was possible when a directory was SGID, belonged to a certain group and was writable by a user who was not a member of this group. This could lead to excessive permissions granted in case when they should not. (CVE-2018-13405)
[Moderate] A flaw was discovered in the implementation of SCTP protocol. A local unprivileged user could exploit it to cause soft lockups in the kernel (and, eventually, a denial of service) using specially crafted sequences of system calls. (PSBM-86804)
3. Bug Fixes¶
Kernel warning in kill_block_super() when a mount operation fails. (PSBM-80743)
It was discovered that the system could fail to restore a container (‘VZctlError: Not enough system resources’) if the container had more mounts than one third of the limit shown in /proc/sys/fs/ve-mount-nr. (PSBM-86511)
Missing unlock_page() in the error path in fuse_readpages_fill(). (PSBM-86790)
4. Installing the Update¶
Download, install, and immediately apply the patch to the current kernel by running ‘readykernel update’.
5. References¶
https://readykernel.com/patch/Virtuozzo-7/readykernel-patch-30.10-55.0-1.vl7/
https://readykernel.com/patch/Virtuozzo-7/readykernel-patch-30.15-55.0-1.vl7/
https://readykernel.com/patch/Virtuozzo-7/readykernel-patch-33.22-55.0-1.vl7/
https://readykernel.com/patch/Virtuozzo-7/readykernel-patch-37.30-55.0-1.vl7/
https://readykernel.com/patch/Virtuozzo-7/readykernel-patch-40.4-55.0-1.vl7/
https://readykernel.com/patch/Virtuozzo-7/readykernel-patch-43.10-55.0-1.vl7/
https://readykernel.com/patch/Virtuozzo-7/readykernel-patch-46.7-55.0-1.vl7/
https://readykernel.com/patch/Virtuozzo-7/readykernel-patch-48.2-55.0-1.vl7/
The JSON file with the list of new and updated packages is available at http://docs.virtuozzo.com/vza/VZA-2018-049.json.