CVE-2017-7358 : Security Advisory and Response

LightDM through version 1.22.0 is vulnerable to a directory traversal issue that allows local attackers to gain control over directory paths and escalate privileges to root.

Understanding CVE-2017-7358

This CVE involves a security vulnerability in LightDM versions up to 1.22.0 that can be exploited by local attackers to elevate privileges.

What is CVE-2017-7358?

The vulnerability in LightDM versions up to 1.22.0 allows local attackers to manipulate directory paths and gain root privileges after the guest user logs out. The issue specifically occurs in debian/guest-account.sh due to a directory traversal flaw.

The Impact of CVE-2017-7358

The vulnerability enables attackers to take control of arbitrary directory paths and escalate their privileges to root level, posing a significant security risk to affected systems.

Technical Details of CVE-2017-7358

LightDM through version 1.22.0 is susceptible to a critical security flaw that can be exploited by attackers to compromise system integrity.

Vulnerability Description

The vulnerability in LightDM versions up to 1.22.0 allows local attackers to manipulate directory paths, leading to unauthorized access and privilege escalation to root level.

Affected Systems and Versions

LightDM versions up to 1.22.0

Exploitation Mechanism

Attackers can exploit the vulnerability by leveraging the directory traversal issue in debian/guest-account.sh, gaining control over directory paths and escalating privileges to root.

Mitigation and Prevention

To address CVE-2017-7358 and enhance system security, follow these mitigation strategies:

Immediate Steps to Take

Update LightDM to a patched version that addresses the directory traversal vulnerability.
Monitor system logs for any suspicious activities related to unauthorized directory access.

Long-Term Security Practices

Implement least privilege access controls to restrict user permissions and prevent unauthorized directory manipulation.
Conduct regular security audits and vulnerability assessments to identify and remediate potential weaknesses.

Patching and Updates

Apply security patches provided by the vendor promptly to mitigate the vulnerability and prevent exploitation.