ACTIVELY EXPLOITED
CVE-2009-3129: Microsoft Excel Featheader Record Memory Corruption Vulnerability
| Vendor | Microsoft |
|---|---|
| Product | Excel |
| Actively exploited | Yes |
| Added to CISA KEV | 3 Mar 2022 |
| CISA federal deadline | 24 Mar 2022 |
| Weakness (CWE) | CWE-94 |
Required action (CISA's text)
Apply updates per vendor instructions.
Description (NVD)
Microsoft Office Excel allows remote attackers to execute arbitrary code via a spreadsheet with a FEATHEADER record containing an invalid cbHdrData size element that affects a pointer offset.
SOURCES
Other Microsoft flaws
- patchtuesday:2026-11: Vulnerability in Microsoft
- CVE-2026-124194: Microsoft Office Outlook Missing User Interaction for Potentially Unsafe Action Vulnerability
- CVE-2026-96951: Microsoft Windows Command Injection Vulnerability
- CVE-2026-65660: Microsoft SharePoint Code Injection Vulnerability
- CVE-2026-85880: Microsoft Windows Heap-Based Buffer Overflow Vulnerability
Data from NVD, CISA KEV, FIRST EPSS and vendor advisories. Updated 10 Nov 2026.