CVE-2025-32705: Out-of-Bounds Read Vulnerability in Microsoft Office Outlook

Overview

CVE-2025-32705 is a critical vulnerability that exposes Microsoft Office Outlook users to potential system compromise and data leakage. The vulnerability lies in an out-of-bounds read error, which, if exploited, allows unauthorized attackers to execute code locally. With the widespread use of Microsoft Office Outlook in organizations worldwide, this vulnerability holds significant implications for data security and privacy, making its understanding and mitigation a top priority for cybersecurity teams.

Vulnerability Summary

CVE ID: CVE-2025-32705
Severity: High (7.8 CVSS score)
Attack Vector: Local
Privileges Required: None
User Interaction: Required
Impact: Potential system compromise or data leakage

Affected Products

Product | Affected Versions

Microsoft Office Outlook | All versions prior to the vendor patch

How the Exploit Works

The vulnerability stems from an out-of-bounds read error in Microsoft Office Outlook. It occurs when the software attempts to access data outside the boundaries of a buffer-a block of computer memory set aside for temporary storage. A successful exploit of this vulnerability allows an unauthorized attacker to read sensitive information from other memory locations or cause the application to crash, leading to a denial of service. In some cases, it may also allow the attacker to execute arbitrary code on the victim’s system.

Conceptual Example Code

Let’s consider a scenario where an attacker sends a malicious email with specially crafted content. When the victim opens this email in Microsoft Office Outlook, it triggers the out-of-bounds read error, allowing the attacker to execute arbitrary code. The malicious payload might look something like this:

POST /malicious/email HTTP/1.1
Host: target.example.com
Content-Type: text/html
{ "malicious_content": "<script>arbitrary_code_here</script>" }

In this example, the arbitrary code executed could vary based on the attacker’s objectives, which could range from system compromise to data theft.

Mitigation Guidance

To mitigate this vulnerability, users are strongly advised to apply the vendor patch as soon as it becomes available. Until then, organizations can use Web Application Firewalls (WAF) or Intrusion Detection Systems (IDS) as a temporary mitigation measure. These solutions can help detect and block malicious activities related to this vulnerability. Regularly updating and patching software, educating users about the risks of opening suspicious emails, and implementing robust cybersecurity policies can also help in preventing such exploits.