VDB-369671 · CVE-2026-45463 · GCVE-0-2026-45463

Microsoft Office up to LTSC 2024 integer underflow

CVSS Meta Temp Score CVSS is a standardized scoring system to determine possibilities of attacks. The Temp Score considers temporal factors like disclosure, exploit and countermeasures. The unique Meta Score calculates the average score of different sources to provide a normalized scoring system.	Current Exploit Price (≈) Our analysts are monitoring exploit markets and are in contact with vulnerability brokers. The range indicates the observed or calculated exploit price to be seen on exploit markets. A good indicator to understand the monetary effort required for and the popularity of an attack.	CTI Interest Score Our Cyber Threat Intelligence team is monitoring different web sites, mailing lists, exploit markets and social media networks. The CTI Interest Score identifies the interest of attackers and the security community for this specific vulnerability in real-time. A high score indicates an elevated risk to be targeted for this vulnerability.
6.4	$5k-$25k	0.64-

Summaryinfo

A vulnerability, which was classified as critical, has been found in Microsoft Office up to LTSC 2024. Impacted is an unknown function. The manipulation leads to integer underflow. This vulnerability is documented as CVE-2026-45463. The attack can be initiated remotely. There is not any exploit available. It is recommended to apply a patch to fix this issue.

Detailsinfo

A vulnerability was found in Microsoft Office up to LTSC 2024 and classified as critical. This issue affects an unknown functionality. The manipulation with an unknown input leads to a integer underflow vulnerability. Using CWE to declare the problem leads to CWE-191. The product subtracts one value from another, such that the result is less than the minimum allowable integer value, which produces a value that is not equal to the correct result. Impacted is confidentiality, integrity, and availability.

The weakness was released 06/09/2026 as confirmed security update guide (Website). It is possible to read the advisory at msrc.microsoft.com. The identification of this vulnerability is CVE-2026-45463. The exploitation is known to be easy. 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 pricing for an exploit might be around USD $5k-$25k at the moment (estimation calculated on 06/09/2026).

Upgrading to version 16.0.5556.1005 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.

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Productinfo

Type

Office Suite Software

Vendor

Microsoft

Name

Office

Version

License

commercial

Website

Vendor: https://www.microsoft.com/

CPE 2.3info

CPE 2.2info

CVSSv4info

VulDB Vector: 🔒
VulDB Reliability: 🔍

CVSSv3info

VulDB Meta Base Score: 7.3
VulDB Meta Temp Score: 6.4

VulDB Base Score: 6.3
VulDB Temp Score: 5.5
VulDB Vector: 🔒
VulDB Reliability: 🔍

Vendor Base Score (Microsoft): 8.4
Vendor Vector (Microsoft): 🔒

CVSSv2info

AV	AC	Au	C	I	A
💳	💳	💳	💳	💳	💳
💳	💳	💳	💳	💳	💳
💳	💳	💳	💳	💳	💳

Vector	Complexity	Authentication	Confidentiality	Integrity	Availability
Unlock	Unlock	Unlock	Unlock	Unlock	Unlock
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Unlock	Unlock	Unlock	Unlock	Unlock	Unlock

VulDB Base Score: 🔒
VulDB Temp Score: 🔒
VulDB Reliability: 🔍

Exploitinginfo

Class: Integer underflow
CWE: CWE-191 / CWE-189
CAPEC: 🔒
ATT&CK: 🔒

Physical: Partially
Local: Yes
Remote: Yes

Availability: 🔒
Status: Unproven
Price Prediction: 🔍
Current Price Estimation: 🔒

0-Day	Unlock	Unlock	Unlock	Unlock
Today	Unlock	Unlock	Unlock	Unlock

Threat Intelligenceinfo

Interest: 🔍
Active Actors: 🔍
Active APT Groups: 🔍

Countermeasuresinfo

Recommended: Patch
Status: 🔍

Reaction Time: 🔒
0-Day Time: 🔒
Exposure Time: 🔒

Upgrade: Office 16.0.5556.1005

Timelineinfo

06/09/2026 VulDB entry created
06/09/2026 +0 days Advisory disclosed
06/09/2026 +0 days Countermeasure disclosed
06/09/2026 +0 days VulDB entry last update