VDB-369706 · CVE-2026-45596 · GCVE-0-2026-45596

Microsoft Windows up to Server 2025 Ancillary Function Driver for WinSock use after free

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.
6.1	$5k-$25k	1.91-

Summaryinfo

A vulnerability categorized as critical has been discovered in Microsoft Windows. The impacted element is an unknown function of the component Ancillary Function Driver for WinSock. Executing a manipulation can lead to use after free. This vulnerability is handled as CVE-2026-45596. It is possible to launch the attack on the local host. There is not any exploit available. It is advisable to upgrade the affected component.

Detailsinfo

A vulnerability has been found in Microsoft Windows and classified as critical. This vulnerability affects an unknown functionality of the component Ancillary Function Driver for WinSock. The manipulation with an unknown input leads to a use after free vulnerability. The CWE definition for the vulnerability is CWE-416. Referencing memory after it has been freed can cause a program to crash, use unexpected values, or execute code. As an impact it is known to affect confidentiality, integrity, and availability.

The weakness was released 06/09/2026 as confirmed security update guide (Website). The advisory is available at msrc.microsoft.com. This vulnerability was named CVE-2026-45596. The exploitation appears to be difficult. Local access is required to approach this attack. The technical details are unknown and an exploit is not available. The structure of the vulnerability defines a possible price range of USD $5k-$25k at the moment (estimation calculated on 06/09/2026).

Upgrading to version 10.0.17763.8880 eliminates this vulnerability. A possible mitigation has been published immediately after the disclosure of the vulnerability.

If you want to get best quality of vulnerability data, you may have to visit VulDB.

Productinfo

Type

Operating System

Vendor

Microsoft

Name

Windows

Version

License

commercial

Website

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

CPE 2.3info

CPE 2.2info

CVSSv4info

VulDB Vector: 🔒
VulDB Reliability: 🔍

CVSSv3info

VulDB Meta Base Score: 7.0
VulDB Meta Temp Score: 6.1

VulDB Base Score: 7.0
VulDB Temp Score: 6.1
VulDB Vector: 🔒
VulDB Reliability: 🔍

Vendor Base Score (Microsoft): 7.0
Vendor Vector (Microsoft): 🔒

CVSSv2info

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

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

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

Exploitinginfo

Class: Use after free
CWE: CWE-416 / CWE-119
CAPEC: 🔒
ATT&CK: 🔒

Physical: Partially
Local: Yes
Remote: No

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: Upgrade
Status: 🔍

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

Upgrade: Windows 10.0.17763.8880

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