SB2018010921 - Ubuntu update for Linux kernel
Published: January 9, 2018
Breakdown by Severity
- Low
- Medium
- High
- Critical
Description
This security bulletin contains information about 5 secuirty vulnerabilities.
1) Information disclosure (CVE-ID: CVE-2017-5754)
The vulnerability allows a local attacker to obtain potentially sensitive information.
The vulnerability exists in Intel CPU hardware due to side-channel attacks, which are also referred to as Meltdown attacks. A local attacker can execute arbitrary code, perform a side-channel analysis of the data cache and gain access to sensitive information including memory from the CPU cache.
2) Privilege escalation (CVE-ID: CVE-2017-17863)
The vulnerability allows a local attacker to gain elevated privileges on the target system.The weakness exists due to kernel/bpf/verifier.c in the Linux kernel does not check the relationship between pointer values and the BPF stack. A local attacker can run a specially crafted application to trigger integer overflow or invalid memory access and execute arbitrary code with root privileges.
Successful exploitation of the vulnerability may result in system compromise.
3) Memory corruption (CVE-ID: CVE-2017-16995)
The vulnerability allows a local attacker to cause DoS condition or execute arbitrary code on the target system.The weakness exists in the check_alu_op function due to boundary error. A local attacker can trigger memory corruption, cause the service to crash or execute arbitrary code.
Successful exploitation of the vulnerability may result in system compromise.
4) Denial of service (CVE-ID: CVE-2017-17862)
The vulnerability allows a local attacker to cause DoS condition on the target system.The weakness exists due to kernel/bpf/verifier.c in the Linux kernel improperly explores unreachable code paths, even though it would still be processed by JIT compilers. A local attacker can run a specially crafted application, trigger an improper branch-pruning logic issue and cause the system to crash.
Successful exploitation of the vulnerability results in denial of service.
5) Memory leak (CVE-ID: CVE-2017-17864)
The vulnerability allows a local attacker to obtain potentially sensitive information on the target system.The weakness exists due to kernel/bpf/verifier.c in the Linux kernel mishandles states_equal comparisons between the pointer data type and the UNKNOWN_VALUE data type. A local attacker can trigger a memory leak and obtain potentially sensitive address information.
Remediation
Install update from vendor's website.