SB2018120713 - Amazon Linux AMI update for zsh
Published: December 7, 2018
Breakdown by Severity
- Low
- Medium
- High
- Critical
Description
This security bulletin contains information about 8 secuirty vulnerabilities.
1) Stack-based buffer overflow (CVE-ID: CVE-2018-1100)
The vulnerability allows a local attacker to gain elevated privileges on the target system.
The vulnerability exists due to stack-based buffer overflow in the utils.c:checkmailpath function. A local attacker can trigger memory corruption and execute arbitrary code with elevated privileges.
Successful exploitation of this vulnerability may result in complete compromise of vulnerable system.
2) Stack-based buffer overflow (CVE-ID: CVE-2018-1071)
The vulnerability allows a local attacker to cause DOS condition on the target system.The weakness exists in the exec.c:hashcmd() function due to stack-based buffer overflow. A local attacker can trigger memory corruption and cause the service to crash.
3) NULL pointer dereference (CVE-ID: CVE-2017-18205)
The vulnerability allows a local unauthenticated attacker to cause DoS condition on the target system.The weakness exists due to a NULL pointer dereference when processing a cd command while in sh compatibility mode. A local attacker can cause the service to crash.
4) Buffer overflow (CVE-ID: CVE-2017-18206)
The vulnerability allows a local attacker to cause DoS condition on the target system.The weakness exists in the utils.c source code file due to insufficient checks on buffer lengths for symlink expansion. A local attacker can send specially crafted input, trigger memory corruption and cause the service to crash.
5) Buffer overflow (CVE-ID: CVE-2014-10071)
The vulnerability allows a local attacker to cause DoS condition on the target system.The weakness exists in the exec.c source code file due to buffer overflow. A local attacker can send long file descriptors (fds), in the >& fd syntax, trigger memory corruption and cause the service to crash.
6) Improper input validation (CVE-ID: CVE-2018-7549)
The vulnerability allows a local attacker to cause DoS condition on the target system.The weakness exists in the params.c source code file due to improper handling of hash tables. A local attacker can copy an empty hash table with the typeset -p command and cause the service to crash.
7) Buffer overflow (CVE-ID: CVE-2014-10072)
The vulnerability allows a local unauthenticated attacker to cause DoS condition on the target system.The weakness exists in the utils.c source code file due to buffer overflow. A local attacker can trigger memory corruption and cause the service to crash.
8) Buffer overflow (CVE-ID: CVE-2018-1083)
The vulnerability allows a local attacker to gain elevated privileges on the target system.The weakness exists in the compctl.c source code file due to insufficient bounds checking on the PATH_MAX-sized buffer used for file completion candidates. A local attacker can create a malicious directory path, trick the victim into using the autocomplete functionality to traverse the path, trigger buffer overflow and execute arbitrary code with root privileges.
Successful exploitation of the vulnerability may result in system compromise.
Remediation
Install update from vendor's website.