CVE-2020-35766 Explained : Impact and Mitigation
Learn about CVE-2020-35766, a vulnerability in OpenDKIM through 2.10.3 allowing local users to gain privileges via a symlink attack. Find mitigation steps and long-term security practices here.
OpenDKIM through version 2.10.3 is vulnerable to a privilege escalation issue due to a symlink attack in the test suite. This CVE allows local users to gain elevated privileges by exploiting the /tmp/testkeys file.
Understanding CVE-2020-35766
This CVE pertains to a security vulnerability in the OpenDKIM software that can be exploited by local users to escalate their privileges.
What is CVE-2020-35766?
The vulnerability in the test suite of libopendkim in OpenDKIM through version 2.10.3 enables local users to gain elevated privileges through a symlink attack on the /tmp/testkeys file.
The Impact of CVE-2020-35766
The vulnerability poses a security risk as it allows unauthorized users to escalate their privileges on the system, potentially leading to unauthorized access and malicious activities.
Technical Details of CVE-2020-35766
OpenDKIM through version 2.10.3 is susceptible to a symlink attack in the test suite, leading to privilege escalation.
Vulnerability Description
The issue arises from inadequate handling of symlinks in the /tmp/testkeys file within the test suite of libopendkim, allowing local users to exploit it for privilege escalation.
Affected Systems and Versions
- Product: OpenDKIM
- Vendor: N/A
- Versions affected: All versions through 2.10.3
Exploitation Mechanism
By creating a symlink attack against the /tmp/testkeys file, local users can manipulate the system to gain elevated privileges.
Mitigation and Prevention
To address CVE-2020-35766, users and administrators should take immediate steps to mitigate the risk and implement long-term security practices.
Immediate Steps to Take
- Disable unnecessary services and restrict access to critical files and directories.
- Regularly monitor system logs for any suspicious activities.
- Apply the latest security patches and updates for OpenDKIM.
Long-Term Security Practices
- Implement the principle of least privilege to limit user access rights.
- Conduct regular security audits and penetration testing to identify and address vulnerabilities.
- Educate users on best practices for secure file handling and symlink protection.
Patching and Updates
- Stay informed about security advisories related to OpenDKIM and promptly apply patches released by the vendor to address known vulnerabilities.