The Red Hat module-setup.sh script for kexec-tools, as distributed in the kexec-tools before 2.0.7-19 packages in Red Hat Enterprise Linux, allows local users to write to arbitrary files via a symlink attack on a temporary file.

It was found that the module-setup.sh script provided by kexec-tools created temporary files in an insecure way. A malicious, local user could use this flaw to conduct a symbolic link attack, allowing them to overwrite the contents of arbitrary files. (CVE-2015-0267)

This update also fixes the following bug :

  - On Atomic Host systems, the kdump tool previously saved     kernel crash dumps in the /sysroot/crash file instead of     the /var/crash file. The parsing error that caused this     problem has been fixed, and the kernel crash dumps are     now correctly saved in /var/crash.

In addition, this update adds the following enhancement :

  - The makedumpfile command now supports the new sadump     format that can represent more than 16 TB of physical     memory space. This allows users of makedumpfile to read     dump files over 16 TB, generated by sadump on certain     upcoming server models.

Updated kexec-tools packages that fix one security issue, one bug, and add one enhancement are now available for Red Hat Enterprise Linux 7.

Red Hat Product Security has rated this update as having Moderate security impact. A Common Vulnerability Scoring System (CVSS) base score, which gives a detailed severity rating, is available from the CVE link in the References section.

The kexec-tools packages contain the /sbin/kexec binary and utilities that together form the user-space component of the kernel's kexec feature. The /sbin/kexec binary facilitates a new kernel to boot using the kernel's kexec feature either on a normal or a panic reboot. The kexec fastboot mechanism allows booting a Linux kernel from the context of an already running kernel.

It was found that the module-setup.sh script provided by kexec-tools created temporary files in an insecure way. A malicious, local user could use this flaw to conduct a symbolic link attack, allowing them to overwrite the contents of arbitrary files. (CVE-2015-0267)

This issue was discovered by Harald Hoyer of Red Hat.

This update also fixes the following bug :

* On Red Hat Enterprise Linux Atomic Host systems, the kdump tool previously saved kernel crash dumps in the /sysroot/crash file instead of the /var/crash file. The parsing error that caused this problem has been fixed, and the kernel crash dumps are now correctly saved in /var/crash. (BZ#1206464)

In addition, this update adds the following enhancement :

* The makedumpfile command now supports the new sadump format that can represent more than 16 TB of physical memory space. This allows users of makedumpfile to read dump files over 16 TB, generated by sadump on certain upcoming server models. (BZ#1208753)

All kexec-tools users are advised to upgrade to these updated packages, which contain backported patches to correct these issues and add this enhancement.

The remote Oracle Linux 7 host has packages installed that are affected by a vulnerability as referenced in the ELSA-2015-0986 advisory.

    [2.0.7-19.0.1.el7_1.2]
    - kdumpctl: exclude default_hugepagesz setting from kdump kernel cmdline      (Sriharsha Yadagudde) [Orabug: 19134999]
    - kdumpctl: verify if kernel support securelevel interface       (Sriharsha Yadagudde) [Orabug: 18905671]

    [2.0.7-19.2]
    - dracut-module-setup: Enhance kdump to support the bind mounted feature in Atomic
    - Fix the warning if the target path is bind mount in Atomic
    - Get the mount point correctly, if the device has several mount point
    - kdump-lib: Add new function to judge the system is Atomic or not
    - kdump-lib: Add the new function to enhance bind mounted judgement
    - Remove duplicate slash in save path
    - dracut-module-setup.sh: change the insecure use of /tmp/*9947* filenames

    [2.0.7-19.1]
    - sadump: Support more than 16TB physical memory space.

Tenable has extracted the preceding description block directly from the Oracle Linux security advisory.

Note that Nessus has not tested for this issue but has instead relied only on the application's self-reported version number.

ID	Name	Product	Family	Severity
83452	Scientific Linux Security Update : kexec-tools on SL7.x x86_64 (20150512)	Nessus	Scientific Linux Local Security Checks	low
83407	RHEL 7 : kexec-tools (RHSA-2015:0986)	Nessus	Red Hat Local Security Checks	low
83401	Oracle Linux 7 : kexec-tools (ELSA-2015-0986)	Nessus	Oracle Linux Local Security Checks	medium
83377	CentOS 7 : kexec-tools (CESA-2015:0986)	Nessus	CentOS Local Security Checks	low

Detections

Analytics

CVE-2015-0267

critical

Tenable Plugins

low

low

medium

low