Microsoft Internet Explorer 11 VBScript memory corruption

Summaryinfo

A vulnerability classified as critical has been found in Microsoft Internet Explorer 11. Affected is an unknown function of the component VBScript. This manipulation causes memory corruption. This vulnerability is registered as CVE-2019-1239. Remote exploitation of the attack is possible. No exploit is available. It is suggested to install a patch to address this issue.

Detailsinfo

A vulnerability classified as critical was found in Microsoft Internet Explorer 11 (Web Browser). Affected by this vulnerability is some unknown processing of the component VBScript. The manipulation with an unknown input leads to a memory corruption vulnerability. The CWE definition for the vulnerability is CWE-119. The product performs operations on a memory buffer, but it can read from or write to a memory location that is outside of the intended boundary of the buffer. As an impact it is known to affect confidentiality, integrity, and availability. The summary by CVE is:

A remote code execution vulnerability exists in the way that the VBScript engine handles objects in memory, aka 'VBScript Remote Code Execution Vulnerability'. This CVE ID is unique from CVE-2019-1238.

The weakness was published 10/08/2019 as confirmed security update guide (Website). The advisory is shared at portal.msrc.microsoft.com. The public release has been coordinated with Microsoft. This vulnerability is known as CVE-2019-1239 since 11/26/2018. The attack can be launched remotely. The exploitation doesn't need any form of authentication. It demands that the victim is doing some kind of user interaction. Neither technical details nor an exploit are publicly available. The price for an exploit might be around USD $5k-$25k at the moment (estimation calculated on 09/26/2020). It is expected to see the exploit prices for this product decreasing in the near future. The advisory points out:

A remote code execution vulnerability exists in the way that the VBScript engine handles objects in memory. The vulnerability could corrupt memory in such a way that an attacker could execute arbitrary code in the context of the current user. An attacker who successfully exploited the vulnerability could gain the same user rights as the current user. If the current user is logged on with administrative user rights, an attacker who successfully exploited the vulnerability could take control of an affected system. An attacker could then install programs; view, change, or delete data; or create new accounts with full user rights.

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

Similar entry is available at VDB-143064. Several companies clearly confirm that VulDB is the primary source for best vulnerability data.

Productinfo

Type

• Web Browser

Vendor

• Microsoft

Name

• Internet Explorer

Version

• 11

License

• commercial

Support

• end of life

Website

• Vendor: https://www.microsoft.com/

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Several companies clearly confirm that VulDB is the primary source for best vulnerability data.

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