Microsoft Windows contains a vulnerability that could allow an unauthenticated, remote attacker to bypass security restrictions. Updates are available.
Microsoft Windows contains a vulnerability that could allow an unauthenticated, remote attacker to bypass security restrictions.
The vulnerability is due to improper handling of SSL version 3 (SSLv3) and Transport Layer Security (TLS) session version negotiation by the affected software. An unauthenticated, remote attacker who has successfully intercepted web traffic handshakes could exploit the vulnerability by injecting crafted content into an SSL/TLS session. If successful, the attacker could bypass security restrictions in SSLv3 by downgrading to SSLv2.
Microsoft confirmed the vulnerability in a security bulletin and released software updates.
The following Microsoft products are vulnerable:
Windows Vista SP2
Windows Vista x64 Edition SP2
Windows Server 2008 for 32-bit Systems SP2
Windows Server 2008 for x64-based Systems SP2
Windows Server 2008 for Itanium-based Systems SP2
Windows 7 for 32-bit Systems SP1 and prior
Windows 7 for x64-based Systems SP1 and prior
Windows Server 2008 R2 for x64-based Systems SP1 and prior
Windows Server 2008 R2 for Itanium-based Systems SP1 and prior
Windows 8 for 32-bit Systems
Windows 8 for x64-based Systems
Windows Server 2012
To exploit this vulnerability, an attacker must intercept an SSL/TLS session, possibly by performing a man-in-the-middle attack against the targeted system. This requirement decreases the likelihood of a successful exploit.
Microsoft has corrected this vulnerability by modifying the way the Windows SSL provider component handles encrypted network packets.
Microsoft has released a security bulletin at the following link: MS13-006
An unauthenticated, remote attacker could exploit this vulnerability to downgrade an SSLv3 or TLS connection to SSLv2, which could weaken security on an affected system.
The vulnerability is due to improper handling of SSLv3 and TLS session version negotiation by the affected software while encrypting network traffic.
An unauthenticated, remote attacker who has successfully intercepted web traffic handshakes could exploit the vulnerability by injecting crafted content into an SSL/TLS session. If successful, the attacker could bypass security restrictions in SSLv3 by downgrading to SSLv2.
Administrators are advised to apply the appropriate updates.
Administrators are advised to allow only trusted users to have network access.
Administrators may consider disabling SSLv2 in Internet Explorer and Internet Information Services (IIS).
Administrators are advised to monitor affected systems.
Microsoft customers can obtain updates directly by using the links in the security bulletin. These updates are also distributed by Windows automatic update features and available on the Microsoft Update service. Microsoft Windows Server Update Services (WSUS), Systems Management Server, and System Center Configuration Manager can assist administrators in deploying software updates.
The security vulnerability applies to the following combinations of products.
for 32-bit systemsBase, SP1 | for x64-based systemsBase, SP1 | Original ReleaseBase | Datacenter EditionSP2 | Datacenter Edition, 64-bitSP2 | Itanium-Based Systems EditionSP2 | Enterprise EditionSP2 | Enterprise Edition, 64-bitSP2 | Essential Business Server StandardSP2 | Essential Business Server PremiumSP2 | Essential Business Server Premium, 64-bitSP2 | Standard EditionSP2 | Standard Edition, 64-bitSP2 | Web ServerSP2 | Web Server, 64-bitSP2 | x64-Based Systems EditionBase, SP1 | Itanium-Based Systems EditionBase, SP1 | Original ReleaseBase | Home BasicSP2 | Home PremiumSP2 | BusinessSP2 | EnterpriseSP2 | UltimateSP2 | Home Basic x64 EditionSP2 | Home Premium x64 EditionSP2 | Business x64 EditionSP2 | Enterprise x64 EditionSP2 | Ultimate x64 EditionSP2 | for 32-bit systemsBase | for x64-based systemsBase
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