CVE-2018-7757 : Vulnerability Insights and Analysis

The Linux kernel version 4.15.7 has a vulnerability in the sas_smp_get_phy_events function, leading to a memory leak. This flaw allows local users to trigger a denial of service attack by excessively consuming memory through read operations on files within the /sys/class/sas_phy directory.

Understanding CVE-2018-7757

This CVE entry highlights a memory leak vulnerability in the Linux kernel version 4.15.7.

What is CVE-2018-7757?

The vulnerability in the sas_smp_get_phy_events function of the Linux kernel version 4.15.7 results in a memory leak. Local users can exploit this flaw to cause a denial of service by performing multiple read operations on specific files.

The Impact of CVE-2018-7757

The vulnerability allows attackers to exhaust system memory, leading to a denial of service condition. By manipulating certain files in the /sys/class/sas_phy directory, attackers can disrupt system operations.

Technical Details of CVE-2018-7757

This section provides detailed technical information about the vulnerability.

Vulnerability Description

The sas_smp_get_phy_events function in the Linux kernel through version 4.15.7 allows local users to trigger a denial of service attack by causing excessive memory consumption through read accesses to files in the /sys/class/sas_phy directory.

Affected Systems and Versions

Affected System: Linux kernel version 4.15.7
Affected Component: sas_smp_get_phy_events function

Exploitation Mechanism

Attackers can exploit this vulnerability by performing multiple read operations on files within the /sys/class/sas_phy directory, such as the /sys/class/sas_phy/phy-1:0:12/invalid_dword_count file.

Mitigation and Prevention

Protecting systems from CVE-2018-7757 requires immediate actions and long-term security practices.

Immediate Steps to Take

Apply patches provided by the Linux kernel maintainers promptly.
Monitor system resources for unusual memory consumption.
Restrict access to sensitive system directories like /sys/class/sas_phy.

Long-Term Security Practices

Regularly update the Linux kernel to the latest stable version.
Implement least privilege access controls to limit user capabilities.
Conduct regular security audits to identify and address vulnerabilities.

Patching and Updates

Linux kernel patches addressing CVE-2018-7757 are available from the official Linux kernel repository.