CVE-2009-3677
The Internet Authentication Service (IAS) in Microsoft Windows 2000 SP4, XP SP2 and SP3, Server 2003 SP2, Vista Gold and SP1, and Server 2008 Gold does not properly verify the credentials in an MS-CHAP v2 Protected Extensible Authentication Protocol (PEAP) authentication request, which allows remote attackers to access network resources via a malformed request, aka "MS-CHAP Authentication Bypass Vulnerability."
Published:Dec 9, 2009
Last Modified:Apr 23, 2026
EPS:Dec 9, 2009
EPSS Score:0.66697
CVSS Score:10
Affected Products
Vendor
Product
Action
Vendor
Microsoft
Product
Windows 2000
Microsoft
Windows 2000
Vendor
Microsoft
Product
Windows Server 2003
Microsoft
Windows Server 2003
Vendor
Microsoft
Product
Windows Server 2008
Microsoft
Windows Server 2008
Vendor
Microsoft
Product
Windows Vista
Microsoft
Windows Vista
Vendor
Microsoft
Product
Windows Xp
Microsoft
Windows Xp
Exploits
No exploit reference
Common Weakness Enumeration
Common Attack Pattern Enumeration and Classification (CAPEC)
Related CVEs
References
Common Vulnerability Scoring System
Attack Vector
Network
Adjacent
Local
Physical
Privileges Required
None
Low
High
User Interaction
None
Required
Scope
Unchanged
Changed
Confidentiality
None
Low
High
Integrity
None
Low
High
Availability
None
Low
High
