#security-update

#security-update

Microsoft has released emergency out-of-band security updates to fix an actively exploited zero-day vulnerability in Microsoft Office. The flaw allows threat actors to bypass built-in Office security protections after tricking users into opening malicious files, typically delivered through phishing or social engineering. The vulnerability "... in Microsoft Office allows an unauthorized attacker to bypass a security feature locally," Microsoft said in its advisory.

Tracked as CVE-2025-43400, the security defect is described as an out-of-bounds write issue in the operating system's FontParser component that could lead to a denial-of-service (DoS) condition or memory corruption. "Processing a maliciously crafted font may lead to unexpected app termination or corrupt process memory," Apple explains. According to advisories from the Hong Kong CERT and Akaoma Cybersecurity, the vulnerability can be exploited remotely, without privileges, although user interaction is required.