CVE-2017-15671 Explained : Impact and Mitigation

CVE-2017-15671, published on October 20, 2017, addresses a memory leak vulnerability in the GNU C Library (glibc) prior to version 2.27. This vulnerability in the glob function could be exploited to cause a denial of service.

Understanding CVE-2017-15671

This CVE entry highlights a memory leak issue in the glob function of glibc, potentially leading to a denial of service when processing the ~ operator with a lengthy user name.

What is CVE-2017-15671?

The vulnerability in the glob function of glibc before version 2.27 could result in allocated memory not being freed when processing the ~ operator with a long user name, leading to a denial of service due to memory leaks.

The Impact of CVE-2017-15671

The exploitation of this vulnerability could result in a denial of service condition, affecting the availability of the system.

Technical Details of CVE-2017-15671

This section provides more in-depth technical insights into the vulnerability.

Vulnerability Description

The glob function in glob.c of glibc before version 2.27, when used with GLOB_TILDE, could skip freeing allocated memory when processing the ~ operator with a long user name, potentially causing a denial of service due to memory leaks.

Affected Systems and Versions

Systems using GNU C Library (glibc) versions prior to 2.27

Exploitation Mechanism

The vulnerability can be exploited by invoking the glob function with GLOB_TILDE and providing a lengthy user name, causing allocated memory to be skipped from being freed.

Mitigation and Prevention

To address CVE-2017-15671 and enhance system security, consider the following mitigation strategies:

Immediate Steps to Take

Update to version 2.27 or later of the GNU C Library (glibc) to mitigate the memory leak issue.
Monitor for any abnormal system behavior that could indicate a denial of service attack.

Long-Term Security Practices

Regularly update software and libraries to the latest versions to patch known vulnerabilities.
Implement proper input validation to prevent malicious inputs that could trigger memory leaks.

Patching and Updates

Apply patches provided by the GNU C Library (glibc) to address the memory leak vulnerability.