SB2025081302 - Multiple vulnerabilities in Microsoft Windows Ancillary Function Driver for WinSock
Published: August 13, 2025
Breakdown by Severity
- Low
- Medium
- High
- Critical
Description
This security bulletin contains information about 7 vulnerabilities.
1) Use-after-free (CVE-ID: CVE-2025-53718)
CWE-ID: CWE-416 - Use After Free
CVSSv4: CVSS:4.0/AV:L/AC:L/AT:P/PR:L/UI:N/VC:H/VI:H/VA:H/SC:N/SI:N/SA:N/E:U/U:Clear
The vulnerability allows a local user to compromise vulnerable system.
The vulnerability exists due to a use-after-free error in Windows Ancillary Function Driver for WinSock. A local user can gain elevated privileges on the system.
2) Time-of-check Time-of-use (TOCTOU) Race Condition (CVE-ID: CVE-2025-53134)
CWE-ID: CWE-367 - Time-of-check Time-of-use (TOCTOU) Race Condition
CVSSv4: CVSS:4.0/AV:L/AC:L/AT:P/PR:L/UI:N/VC:H/VI:H/VA:H/SC:N/SI:N/SA:N/E:U/U:Clear
The vulnerability allows a local user to compromise the target system.
The vulnerability exists due to a time-of-check, time-of-use (TOCTOU) race condition in Windows Ancillary Function Driver for WinSock. A local user can gain elevated privileges on the target system.
3) Use-after-free (CVE-ID: CVE-2025-53137)
CWE-ID: CWE-416 - Use After Free
CVSSv4: CVSS:4.0/AV:L/AC:L/AT:P/PR:L/UI:N/VC:H/VI:H/VA:H/SC:N/SI:N/SA:N/E:U/U:Clear
The vulnerability allows a local user to compromise vulnerable system.
The vulnerability exists due to a use-after-free error in Windows Ancillary Function Driver for WinSock. A local user can gain elevated privileges on the target system.
4) NULL pointer dereference (CVE-ID: CVE-2025-53141)
CWE-ID: CWE-476 - NULL Pointer Dereference
CVSSv4: CVSS:4.0/AV:L/AC:L/AT:N/PR:L/UI:N/VC:H/VI:H/VA:H/SC:N/SI:N/SA:N/E:U/U:Clear
The vulnerability allows a local user to escalate privileges on the target system.
The vulnerability exists due to a NULL pointer dereference error in Windows Ancillary Function Driver for WinSock. A local user can pass specially crafted data to the application and gain elevated privileges on the target system.
5) Race condition (CVE-ID: CVE-2025-49762)
CWE-ID: CWE-362 - Concurrent Execution using Shared Resource with Improper Synchronization ('Race Condition')
CVSSv4: CVSS:4.0/AV:L/AC:L/AT:P/PR:L/UI:N/VC:H/VI:H/VA:H/SC:N/SI:N/SA:N/E:U/U:Clear
The vulnerability allows a local user to escalate privileges on the system.
The vulnerability exists due to a race condition in Windows Ancillary Function Driver for WinSock. A local user can exploit the race and gain unauthorized access to sensitive information and escalate privileges on the system.
6) Use-after-free (CVE-ID: CVE-2025-53147)
CWE-ID: CWE-416 - Use After Free
CVSSv4: CVSS:4.0/AV:L/AC:L/AT:P/PR:L/UI:N/VC:H/VI:H/VA:H/SC:N/SI:N/SA:N/E:U/U:Clear
The vulnerability allows a local user to escalate privileges on the system.
The vulnerability exists due to a use-after-free error in Windows Ancillary Function Driver for WinSock. A local user can gain elevated privileges on the target system.
7) NULL pointer dereference (CVE-ID: CVE-2025-53154)
CWE-ID: CWE-476 - NULL Pointer Dereference
CVSSv4: CVSS:4.0/AV:L/AC:L/AT:N/PR:L/UI:N/VC:H/VI:H/VA:H/SC:N/SI:N/SA:N/E:U/U:Clear
The vulnerability allows a local user to escalate privileges on the system.
The vulnerability exists due to a NULL pointer dereference error in Windows Ancillary Function Driver for WinSock. A local user can pass specially crafted data to the application and gain elevated privileges on the target system.
Remediation
Install update from vendor's website.
References
- https://msrc.microsoft.com/update-guide/vulnerability/CVE-2025-53718
- https://msrc.microsoft.com/update-guide/vulnerability/CVE-2025-53134
- https://msrc.microsoft.com/update-guide/vulnerability/CVE-2025-53137
- https://msrc.microsoft.com/update-guide/vulnerability/CVE-2025-53141
- https://msrc.microsoft.com/update-guide/vulnerability/CVE-2025-49762
- https://msrc.microsoft.com/update-guide/vulnerability/CVE-2025-53147
- https://msrc.microsoft.com/update-guide/vulnerability/CVE-2025-53154