CVE-2020-25583 : Security Advisory and Response
Learn about CVE-2020-25583, a critical out-of-bounds write vulnerability in FreeBSD versions 12.2-RELEASE, 12.1-RELEASE, and 11.4-RELEASE, potentially leading to remote code execution or denial of service.
In FreeBSD 12.2-STABLE before r368250, 11.4-STABLE before r368253, 12.2-RELEASE before p1, 12.1-RELEASE before p11, and 11.4-RELEASE before p5, a vulnerability exists in the rtsold(8) component that could lead to an out-of-bounds write due to incorrect label length validation.
Understanding CVE-2020-25583
This CVE involves a flaw in the processing of a DNSSL option in FreeBSD, potentially resulting in a buffer overflow due to inadequate label length validation.
What is CVE-2020-25583?
CVE-2020-25583 is a security vulnerability in FreeBSD versions 12.2-RELEASE, 12.1-RELEASE, and 11.4-RELEASE that could allow an attacker to trigger an out-of-bounds write by exploiting the mishandling of domain name labels in the rtsold(8) utility.
The Impact of CVE-2020-25583
The vulnerability could be exploited by a remote attacker to execute arbitrary code or cause a denial of service (DoS) condition on affected systems, potentially leading to a compromise of system integrity.
Technical Details of CVE-2020-25583
The following technical details outline the specifics of the CVE:
Vulnerability Description
- The issue arises from incorrect label length validation in the processing of a DNSSL option in FreeBSD.
Affected Systems and Versions
- FreeBSD 12.2-RELEASE before p1
- FreeBSD 12.1-RELEASE before p11
- FreeBSD 11.4-RELEASE before p5
Exploitation Mechanism
- By sending specially crafted DNSSL options, an attacker could trigger the vulnerability in rtsold(8) and potentially overflow the destination buffer.
Mitigation and Prevention
For users and administrators, it is crucial to take immediate steps to mitigate the risks associated with CVE-2020-25583:
Immediate Steps to Take
- Apply the necessary patches provided by FreeBSD to address the vulnerability.
- Monitor FreeBSD security advisories for updates and follow best security practices.
Long-Term Security Practices
- Regularly update FreeBSD systems to the latest stable releases to ensure all security patches are applied.
- Implement network segmentation and access controls to limit exposure to potential attacks.
Patching and Updates
- Stay informed about security updates from FreeBSD and promptly apply patches to vulnerable systems to prevent exploitation of this vulnerability.