SB2018092812 - Multiple vulnerabilities in FreeBSD



SB2018092812 - Multiple vulnerabilities in FreeBSD

Published: September 28, 2018 Updated: August 8, 2020

Security Bulletin ID SB2018092812
Severity
Medium
Patch available
YES
Number of vulnerabilities 3
Exploitation vector Local access
Highest impact Denial of service

Breakdown by Severity

Medium 67% Low 33%
  • Low
  • Medium
  • High
  • Critical

Description

This security bulletin contains information about 3 secuirty vulnerabilities.


1) NULL pointer dereference (CVE-ID: CVE-2018-17154)

The vulnerability allows a remote attacker to perform a denial of service (DoS) attack.

The vulnerability exists due to a NULL pointer dereference error in FreeBSD before 11.2-STABLE(r338987), 11.2-RELEASE-p4, and 11.1-RELEASE-p15, due to insufficient memory checking in the freebsd4_getfsstat system call, a NULL pointer dereference can occur. Unprivileged authenticated local users may be able to cause a denial of service. A remote attacker can perform a denial of service (DoS) attack.


2) Information disclosure (CVE-ID: CVE-2018-17155)

The vulnerability allows a local authenticated user to gain access to sensitive information.

In FreeBSD before 11.2-STABLE(r338983), 11.2-RELEASE-p4, 11.1-RELEASE-p15, 10.4-STABLE(r338984), and 10.4-RELEASE-p13, due to insufficient initialization of memory copied to userland in the getcontext and swapcontext system calls, small amounts of kernel memory may be disclosed to userland processes. Unprivileged authenticated local users may be able to access small amounts privileged kernel data.


3) NULL pointer dereference (CVE-ID: CVE-2018-6925)

The vulnerability allows a remote attacker to perform a denial of service (DoS) attack.

The vulnerability exists due to a NULL pointer dereference error in FreeBSD before 11.2-STABLE(r338986), 11.2-RELEASE-p4, 11.1-RELEASE-p15, 10.4-STABLE(r338985), and 10.4-RELEASE-p13, due to improper maintenance of IPv6 protocol control block flags through various failure paths, an unprivileged authenticated local user may be able to cause a NULL pointer dereference causing the kernel to crash. A remote attacker can perform a denial of service (DoS) attack.


Remediation

Install update from vendor's website.