cbcvebase.
CVE-2008-3704
published 2008-08-18

CVE-2008-3704: Heap-based buffer overflow in the MaskedEdit ActiveX control in Msmask32.ocx 6.0.81.69, and possibly other versions before 6.0.84.18, in Microsoft Visual…

PriorityP271critical9.3CVSS 2.0
AVNACMAuNCCICAC
ITWEXPLOITVulnCheck KEV
Exploited in the wild
EPSS
55.92%
98.9th percentile
Heap-based buffer overflow in the MaskedEdit ActiveX control in Msmask32.ocx 6.0.81.69, and possibly other versions before 6.0.84.18, in Microsoft Visual Studio 6.0, Visual Basic 6.0, Visual Studio .NET 2002 SP1 and 2003 SP1, and Visual FoxPro 8.0 SP1 and 9.0 SP1 and SP2 allows remote attackers to execute arbitrary code via a long Mask parameter, related to not "validating property values with boundary checks," as exploited in the wild in August 2008, aka "Masked Edit Control Memory Corruption Vulnerability."

Affected

6 ranges
VendorProductVersion rangeFixed in
microsoftvisual_basic
microsoftvisual_foxpro
microsoftvisual_foxpro
microsoftvisual_studio
microsoftvisual_studio_net
microsoftvisual_studio_net

Detection & IOCsextracted from sources · hover to see the quote

filenameMsmask32.ocx
pathC:\WINDOWS\system32\MSMASK32.OCX
other{C932BA85-4374-101B-A56C-00AA003668DC}
versionMsmask32.ocx 6.0.81.69
bytes
%0C (repeated 1945 times as heap spray NOP sled)
  • Detect heap spray patterns using repeated 0x0C bytes (unescape('%0C')) in JavaScript, a technique used in the wild PoC to position shellcode before triggering the overflow via the Mask parameter.
  • Alert on exploitation of the Mask property of the MaskedEdit ActiveX control (Class MaskEdBox, Msmask32.ocx) with an abnormally long string value, which triggers the heap buffer overflow.
  • The Metasploit module targets this vulnerability as a browser exploit delivered over HTTP; monitor for suspicious HTML pages embedding the MaskedEdit ActiveX CLSID with large Mask parameter values.
  • ·Versions of Msmask32.ocx prior to 6.0.84.18 are affected; version 6.0.81.69 is the confirmed vulnerable version. Detections should account for all pre-patch versions.
  • ·The Metasploit module randomizes all JavaScript variable names to evade signature-based detection; string-based JS signatures on variable names will be ineffective. Focus detection on the CLSID and heap spray byte patterns instead.

CVSS provenance

nvdv2.09.3CRITICALAV:N/AC:M/Au:N/C:C/I:C/A:C
vulncheck9.3CRITICAL
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