cbcvebase.
CVE-2009-3129
published 2009-11-11

CVE-2009-3129: Microsoft Office Excel 2002 SP3, 2003 SP3, and 2007 SP1 and SP2; Office 2004 and 2008 for Mac; Open XML File Format Converter for Mac; Office Excel Viewer 2003…

PriorityP185high7.8CVSS 3.1
AVLACLPRNUIRSUCHIHAH
KEVITWEXPLOIT
CISA Known Exploited Vulnerabilitydue 2022-03-24
Exploited in the wild
EPSS
85.73%
99.7th percentile
Microsoft Office Excel 2002 SP3, 2003 SP3, and 2007 SP1 and SP2; Office 2004 and 2008 for Mac; Open XML File Format Converter for Mac; Office Excel Viewer 2003 SP3; Office Excel Viewer SP1 and SP2; and Office Compatibility Pack for Word, Excel, and PowerPoint 2007 File Formats SP1 and SP2 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, aka "Excel Featheader Record Memory Corruption Vulnerability."

Affected

6 ranges
VendorProductVersion rangeFixed in
microsoftexcel
microsoftexcel
microsoftexcel
microsoftexcel_viewer
microsoftoffice
microsoftoffice

Detection & IOCsextracted from sources · hover to see the quote

otherObjPtr=0xdac0ffee (crash/debug marker in malicious XLS)
bytes
04 00 00 00 ee ff c0 da
bytes
\x67\x08 (FEATHEADER record tag 0x0867) followed by 10 null bytes, isf=0x0004, cbHdrData=0x00000004
  • Detect malicious XLS files containing a FEATHEADER (record tag 0x0867) with an anomalous cbHdrData value of 0x00000004 and isf value of 0x0004, which is the exploit trigger condition for CVE-2009-3129.
  • Scan OLE Compound Document (XLS) files for the byte sequence '04 00 00 00 ee ff c0 da' within the Workbook stream, which is a known debug/crash marker used during exploit development targeting this vulnerability.
  • The exploit writes a crafted Workbook stream into an OLE Compound Document with a stream named 'Workbook'; inspect XLS files where the Workbook stream contains record tag 0x0867 (FEATHEADER) with attacker-controlled pointer values immediately following cbHdrData.
  • The Metasploit module sets EXITFUNC to 'process', which is a common shellcode exit strategy; correlate with process-level anomalies in Excel (excel.exe) spawning child processes after opening an XLS file.
  • ·The exploit requires the user to open a malicious XLS file; on some Office versions a warning dialog must be dismissed before the payload executes, reducing silent exploitation success.
  • ·The payload space is limited to 1024 bytes with null bytes as bad characters; shellcode must avoid null bytes and fit within this constraint.

CVSS provenance

nvdv3.17.8HIGHCVSS:3.1/AV:L/AC:L/PR:N/UI:R/S:U/C:H/I:H/A:H
nvdv2.09.3CRITICALAV:N/AC:M/Au:N/C:C/I:C/A:C
vulncheck7.8HIGH
cisa7.8HIGH
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