Security readout for executives and security teams
Plain-English summary
CVE-2026-25178 is a Windows local privilege escalation flaw in the Ancillary Function Driver for WinSock. An attacker already able to run code with low privileges could potentially gain high-level control. It is not a remote entry point, but it matters because it can turn a limited foothold into full system compromise.
Executive priority
Treat this as a high-priority Patch Tuesday item. It is not described as remotely exploitable or actively exploited, but it can materially increase impact after compromise by enabling privilege escalation on Windows systems.
Technical view
Microsoft describes a use-after-free vulnerability in the Windows Ancillary Function Driver for WinSock. CVSS 3.1 is 7.0, with local attack vector, low privileges required, no user interaction, high attack complexity, and high confidentiality, integrity, and availability impact. Affected platforms include multiple Windows 10, Windows 11, and Windows Server releases.
Likely exposure
Exposure is limited to affected Windows endpoints and servers where an attacker already has local authenticated access or code execution. The source bundle lists many supported Windows client and server versions, including Server Core installations.
Exploitation context
No active exploitation is supported by the provided sources. The CVSS vector marks exploit maturity as unproven. This vulnerability is most relevant for post-compromise privilege escalation, malware persistence, or lateral movement after an initial foothold.
Researcher notes
Evidence is limited to the CVE and MSRC advisory data in the source bundle. The vulnerability class is CWE-416 use-after-free in a Windows kernel networking component. Avoid assuming exploit availability, root cause details, or mitigations beyond Microsoft’s published update guidance.
Mitigation direction
- Apply the Microsoft security update referenced in the MSRC advisory.
- Prioritize internet-facing, multi-user, and high-value Windows servers.
- Patch developer workstations, admin workstations, and shared endpoints promptly.
- Check Microsoft guidance for any version-specific prerequisites or supersedence details.
- Monitor MSRC for advisory updates and revised affected-product information.
Validation and detection
- Inventory Windows 10, Windows 11, and Windows Server assets against the affected list.
- Confirm the relevant Microsoft update is installed on each affected system.
- Verify Server Core installations are included in patch compliance reporting.
- Track exceptions where legacy Windows Server versions require special update handling.
- Review vulnerability scanner findings against the MSRC CVE entry.
Public sources used
Generated from the cited source records. This long-tail analysis has not been individually reviewed by a named human.
Conservative CVE-to-ATT&CK context
These mappings and lookup hints may be relevant to the vulnerability behavior, CWE, affected product, or exposure path. Glexia-inferred context is not an official MITRE, ATT&CK, CWE, or CVE Program mapping.
ATT&CK lookup starting points
Use these exact CWE pages and searches to review the Glexia ATT&CK library from this CVE's weakness and description context.
CWE-416: Exact CWE lookup
Use the exact CWE identifier as the starting point before reviewing related ATT&CK behavior. Open the exact CWE lookup page first, then review the ATT&CK searches from that MITRE weakness context. This is a Glexia lookup hint, not an official ATT&CK mapping.
Open ATT&CK lookupPrivilege behavior lookup
The CVE wording references privilege impact, so privilege escalation and authorization behavior review may help. This is a Glexia inferred lookup path, not an official MITRE, ATT&CK, or CVE Program mapping.
Open ATT&CK lookupCVE-2026-25178 mapping review
Open the CVE-to-ATT&CK bridge for reviewed, inferred, or future official mappings tied to this CVE.
Open ATT&CK lookup- Severity
- High
- CVSS
- 7 (3.1)
- Known Exploited
- No
- Published
Vector: CVSS:3.1/AV:L/AC:H/PR:L/UI:N/S:U/C:H/I:H/A:H/E:U/RL:O/RC:C
CNA and ADP enrichment extracted from CVE v5
These fields come from the CVE record and ADP containers, not from Glexia's Take. They preserve time-varying source decisions such as CISA SSVC, KEV status, CVSS metrics, and provider references.
CVSS vector scores
1 official scoreWe collect every scored CVSS vector available in the official CNA and ADP containers. When more than one version is present, the table keeps the source vectors side by side instead of collapsing them into the highest score.
CVSS:3.1/AV:L/AC:H/PR:L/UI:N/S:U/C:H/I:H/A:H/E:U/RL:O/RC:C15.9Primary CVE scoreVulnerability scoring details
Base CVSS 3.1 score
7HighVector: CVSS:3.1/AV:L/AC:H/PR:L/UI:N/S:U/C:H/I:H/A:H/E:U/RL:O/RC:C
Source materials
- CVE List V5 sourceCVE List V5
- Windows Ancillary Function Driver for WinSock Elevation of Privilege VulnerabilityCVE reference · vendor-advisory, patch
Products and packages named in the record
CWE details
CWE links open Glexia weakness intelligence pages with official CWE context, developer remediation guidance, and related CVE mappings.
Use After Free
Use After Free represents a recurring weakness pattern that can create exploitable paths when design, validation, or implementation controls are missing.