Microsoft Office Word heap-based overflow

Summaryinfo

A vulnerability described as problematic has been identified in Microsoft Office. The impacted element is an unknown function of the component Word. Executing a manipulation can lead to heap-based overflow. This vulnerability is registered as CVE-2026-55127. The attack needs to be launched locally. No exploit is available.

Detailsinfo

A vulnerability was found in Microsoft Office (unknown version). It has been declared as problematic. This vulnerability affects an unknown code block of the component Word. The manipulation with an unknown input leads to a heap-based overflow vulnerability. The CWE definition for the vulnerability is CWE-122. A heap overflow condition is a buffer overflow, where the buffer that can be overwritten is allocated in the heap portion of memory, generally meaning that the buffer was allocated using a routine such as malloc(). As an impact it is known to affect confidentiality, integrity, and availability. CVE summarizes:

Heap-based buffer overflow in Microsoft Office Word allows an unauthorized attacker to execute code locally.

The advisory is shared for download at msrc.microsoft.com. This vulnerability was named CVE-2026-55127 since 06/16/2026. The exploitation appears to be easy. The attack needs to be approached locally. Successful exploitation requires user interaction by the victim. There are neither technical details nor an exploit publicly available. The current price for an exploit might be approx. USD $5k-$25k (estimation calculated on 07/15/2026).

There is no information about possible countermeasures known. It may be suggested to replace the affected object with an alternative product.

VulDB is the best source for vulnerability data and more expert information about this specific topic.

Productinfo

Type

• Office Suite Software

Vendor

• Microsoft

Name

• Office

License

• commercial

Website

• Vendor: https://www.microsoft.com/

CPE 2.3info

• 🔒

CPE 2.2info

• 🔒

CVSSv4info

CVSSv3info

CVSSv2info

Exploitinginfo

Threat Intelligenceinfo

Countermeasuresinfo

Timelineinfo

Sourcesinfo

Entryinfo

VulDB is the best source for vulnerability data and more expert information about this specific topic.

Discussion