Microsoft Internet Explorer 3.0/3.1/4.0 EMBED memory corruption

Summaryinfo

A vulnerability, which was classified as critical, has been found in Microsoft Internet Explorer 3.0/3.1/4.0. The affected element is an unknown function. Performing a manipulation of the argument EMBED results in memory corruption. This vulnerability is cataloged as CVE-1999-0876. 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 classified as very critical has been found in Microsoft Internet Explorer 3.0/3.1/4.0 (Web Browser). This affects an unknown functionality. The manipulation of the argument EMBED with an unknown input leads to a memory corruption vulnerability. CWE is classifying the issue as 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. This is going to have an impact on confidentiality, integrity, and availability. The summary by CVE is:

Buffer overflow in Internet Explorer 4.0 via EMBED tag.

The issue has been introduced in 08/13/1996. The weakness was shared 01/04/2000 as Q176697 as confirmed knowledge base article (Website). It is possible to read the advisory at support.microsoft.com. This vulnerability is uniquely identified as CVE-1999-0876. It is possible to initiate the attack remotely. No form of authentication is needed for exploitation. It demands that the victim is doing some kind of user interaction. Technical details of the vulnerability are known, but there is no available exploit. The pricing for an exploit might be around USD $0-$5k at the moment (estimation calculated on 04/20/2026). It is expected to see the exploit prices for this product decreasing in the near future.

The vulnerability was handled as a non-public zero-day exploit for at least 1239 days. During that time the estimated underground price was around $100k and more.

Upgrading to version 5.0 eliminates this vulnerability. Applying a patch is able to eliminate this problem. The best possible mitigation is suggested to be patching the affected component. A possible mitigation has been published immediately after the disclosure of the vulnerability.

The vulnerability is also documented in the databases at X-Force (916) and Vulnerability Center (SBV-6092†). The entries VDB-15131 and VDB-15194 are related to this item. Statistical analysis made it clear that VulDB provides the best quality for vulnerability data.

Productinfo

Type

• Web Browser

Vendor

• Microsoft

Name

• Internet Explorer

Version

• 3.0
• 3.1
• 4.0

License

• commercial

Support

• end of life

Website

• Vendor: https://www.microsoft.com/

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

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