CVE-2020-10255 : What You Need to Know

Modern DRAM chips (DDR4 and LPDDR4 after 2015) are affected by a vulnerability in deployment of internal mitigations against RowHammer attacks known as Target Row Refresh (TRR), aka the TRRespass issue. Attackers can exploit this vulnerability to conduct privilege-escalation attacks and achieve cross-tenant virtual-machine access.

Understanding CVE-2020-10255

This CVE involves a vulnerability in modern DRAM chips that can be exploited to trigger bit flips on affected memory modules, leading to various security risks.

What is CVE-2020-10255?

The vulnerability in the deployment of internal mitigations against RowHammer attacks, known as Target Row Refresh (TRR), allows attackers to manipulate memory modules and conduct privilege-escalation attacks.

The Impact of CVE-2020-10255

Attackers can conduct privilege-escalation attacks against the kernel and the Sudo binary by triggering bit flips on affected memory modules.
The vulnerability enables attackers to achieve cross-tenant virtual-machine access by corrupting RSA keys.

Technical Details of CVE-2020-10255

This section provides more technical insights into the vulnerability.

Vulnerability Description

The vulnerability affects modern DRAM chips, specifically DDR4 and LPDDR4 after 2015, by exploiting the TRR issue to trigger bit flips on memory modules.

Affected Systems and Versions

Chips produced by SK Hynix, Micron, and Samsung are impacted.
Tracking DRAM supply-chain issues is challenging due to potential variations in DRAM chip manufacturers within a single product model.

Exploitation Mechanism

To exploit the vulnerability, attackers need to create specific access patterns to trigger bit flips on affected memory modules, enabling privilege-escalation attacks and unauthorized access.

Mitigation and Prevention

Protecting systems from CVE-2020-10255 requires immediate steps and long-term security practices.

Immediate Steps to Take

Monitor for any unusual memory access patterns that could indicate an ongoing attack.
Implement strict access controls and regularly update security patches.

Long-Term Security Practices

Conduct regular security audits to identify and address vulnerabilities proactively.
Educate users and administrators on secure computing practices to prevent unauthorized access.

Patching and Updates

Apply patches provided by DRAM chip manufacturers promptly to mitigate the vulnerability and enhance system security.