SB2017111605 - Multiple vulnerabilities in FreeBSD
Published: November 16, 2017
Breakdown by Severity
- Low
- Medium
- High
- Critical
Description
This security bulletin contains information about 3 secuirty vulnerabilities.
1) Memory leak (CVE-ID: CVE-2017-1086)
The vulnerability allows a local user to obtain potentially sensitive information.
The vulnerability exists due to an error in implementation of the ptrace(PT_LWPINFO) system call. A local user can use debugger to read portions of data from kernel.
2) Improper access control (CVE-ID: CVE-2017-1087)
The vulnerability allows a local user to access otherwise restricted information.The vulnerability exists due to an error in implementation of POSIX shared memory, intended for realtime inter-process communication by sharing a memory area through the use of a named path. Named paths are globally scoped, meaning a process located in one jail can read and modify the content of POSIX shared memory objects created by a process in another jail or the host system.
A malicious user that has access to a jailed system is able to abuse shared memory by injecting malicious content in the shared memory region. This memory region might be executed by applications trusting the shared memory, like Squid.
Successful exploitation of the vulnerability may allow an attacker to perform a denial of service (DoS) attack or escalate privileges on the system.
3) Memory leak (CVE-ID: CVE-2017-1088)
The vulnerability allows a local user to obtain potentially sensitive information.
The vulnerability exists in kldstat(2) system call implementation due to kernel does not properly clear the memory of the kld_file_stat structure before filling the data. Since the structure filled by the kernel is allocated on the kernel stack and copied to userspace, a leak of information from the kernel stack is possible.
A local user can gain access to potentially sensitive information.
Remediation
Install update from vendor's website.