n10do

Exploited Added to CISA's list January 7, 2026

Microsoft Office: PowerPoint Code Injection Vulnerability

What to do: Update Microsoft Office or Microsoft 365, then restart the apps.

Affects
Microsoft Office
Identifier
CVE-2009-0556
What it is
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.
Official guidance
Apply mitigations per vendor instructions, follow applicable BOD 22-01 guidance for cloud services, or discontinue use of the product if mitigations are unavailable.
Details
National Vulnerability Database entry

"Exploited" means CISA has evidence attackers are using this flaw. Being on the list does not mean your device was attacked; it means the update matters.