ACTIVELY EXPLOITED

CVE-2009-0556: Microsoft Office PowerPoint Code Injection Vulnerability

Facts
VendorMicrosoft
ProductOffice
Actively exploitedYes
Added to CISA KEV7 Jan 2026
CISA federal deadline28 Jan 2026
Weakness (CWE)CWE-94

Required action (CISA's text)

Apply mitigations per vendor instructions, follow applicable BOD 22-01 guidance for cloud services, or discontinue use of the product if mitigations are unavailable.

Description (NVD)

Microsoft Office PowerPoint contains a code injection vulnerability that allows remote attackers to execute arbitrary code via a PowerPoint file with an OutlineTextRefAtom containing an invalid index value that triggers memory corruption.

SOURCES

Other Microsoft flaws

Data from NVD, CISA KEV, FIRST EPSS and vendor advisories. Updated 10 Nov 2026.