Microsoft Windows 7 SP1/Server 2008 R2 SP1/Server 2008 SP2 NTLMv2 inadequate encryption

Summaryinfo

A vulnerability was found in Microsoft Windows 7 SP1/Server 2008 R2 SP1/Server 2008 SP2. It has been classified as critical. Affected by this vulnerability is an unknown functionality of the component NTLMv2. The manipulation leads to inadequate encryption. This vulnerability is traded as CVE-2019-1338. It is possible to initiate the attack remotely. There is no exploit available. To fix this issue, it is recommended to deploy a patch.

Detailsinfo

A vulnerability was found in Microsoft Windows 7 SP1/Server 2008 R2 SP1/Server 2008 SP2 (Operating System). It has been rated as critical. This issue affects an unknown code block of the component NTLMv2. The manipulation with an unknown input leads to a inadequate encryption vulnerability. Using CWE to declare the problem leads to CWE-326. The product stores or transmits sensitive data using an encryption scheme that is theoretically sound, but is not strong enough for the level of protection required. Impacted is confidentiality, integrity, and availability. The summary by CVE is:

A security feature bypass vulnerability exists in Microsoft Windows when a man-in-the-middle attacker is able to successfully bypass the NTLMv2 protection if a client is also sending LMv2 responses, aka 'Windows NTLM Security Feature Bypass Vulnerability'.

The weakness was shared 10/08/2019 as confirmed security update guide (Website). It is possible to read the advisory at portal.msrc.microsoft.com. The vendor cooperated in the coordination of the public release. The identification of this vulnerability is CVE-2019-1338 since 11/26/2018. The exploitation is known to be difficult. The attack may be initiated remotely. No form of authentication is needed for a successful exploitation. It demands that the victim is doing some kind of user interaction. The technical details are unknown and an exploit is not publicly available. The attack technique deployed by this issue is T1600 according to MITRE ATT&CK. The advisory points out:

A security feature bypass vulnerability exists in Microsoft Windows when a man-in-the-middle attacker is able to successfully bypass the NTLMv2 protection if a client is also sending LMv2 responses. An attacker who successfully exploited this vulnerability could gain the ability to downgrade NTLM security features.

Applying a patch is able to eliminate this problem. A possible mitigation has been published immediately after the disclosure of the vulnerability.

The entries VDB-143103, VDB-143102, VDB-143101 and VDB-143100 are related to this item. Statistical analysis made it clear that VulDB provides the best quality for vulnerability data.

Productinfo

Type

• Operating System

Vendor

• Microsoft

Name

• Windows

Version

• 7 SP1
• Server 2008 R2 SP1
• Server 2008 SP2

License

• commercial

Website

• Vendor: https://www.microsoft.com/
• Product: https://www.microsoft.com/en-us/windows

CPE 2.3info

• 🔍
• 🔍
• 🔍

CPE 2.2info

• 🔍
• 🔍
• 🔍

CVSSv4info

CVSSv3info

CVSSv2info

Exploitinginfo

Threat Intelligenceinfo

Countermeasuresinfo

Timelineinfo

Sourcesinfo

Entryinfo

Statistical analysis made it clear that VulDB provides the best quality for vulnerability data.

Discussion