Security readout for executives and security teams
Plain-English summary
This is a Microsoft Windows information disclosure flaw in the WLAN AutoConfig Service. A local user with low privileges could potentially read sensitive information from memory. It is not a remote takeover issue, but it may expose data that helps further compromise a device.
Executive priority
Treat this as a routine but real Windows patching priority. It is not currently evidenced as exploited, but confidentiality impact is high and affected Windows coverage is broad.
Technical view
CVE-2025-21257 is a CWE-125 out-of-bounds read in Windows WLAN AutoConfig Service. CVSS 3.1 is 5.5: local attack vector, low complexity, low privileges required, no user interaction, high confidentiality impact, and no integrity or availability impact.
Likely exposure
Exposure is likely on affected Windows 10, Windows 11, and Windows Server releases listed by Microsoft, including Server Core variants. The source bundle does not specify whether WLAN AutoConfig must be enabled or configured in a particular way.
Exploitation context
The CVSS vector supports only local, authenticated exploitation with no user interaction. KEV status is false, and the provided sources do not claim active exploitation or public exploit availability.
Researcher notes
Evidence is limited to public CVE and Microsoft advisory metadata. The bundle supports local low-privilege exploitation, CWE-125, official remediation availability, and high confidentiality impact, but not exploit mechanics, leaked data type, or active abuse.
Mitigation direction
- Apply Microsoft security updates for CVE-2025-21257 on affected Windows systems.
- Use MSRC guidance to confirm the correct update for each Windows version.
- Prioritize shared workstations, jump hosts, and servers with many local users.
- Monitor Microsoft guidance for revised affected versions or mitigations.
Validation and detection
- Inventory Windows 10, Windows 11, and Windows Server builds against Microsoft’s affected list.
- Check patch management records for the MSRC update addressing CVE-2025-21257.
- Confirm vulnerability scanners no longer report CVE-2025-21257 after patching.
- Review exceptions for unsupported or deferred-update systems.
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-125: 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 lookupCVE-2025-21257 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
- Medium
- CVSS
- 5.5 (3.1)
- Known Exploited
- No
- Published
Vector: CVSS:3.1/AV:L/AC:L/PR:L/UI:N/S:U/C:H/I:N/A:N/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.
SSVC decision data
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:L/PR:L/UI:N/S:U/C:H/I:N/A:N/E:U/RL:O/RC:C1.83.6microsoftVulnerability scoring details
Base CVSS 3.1 score
5.5MediumVector: CVSS:3.1/AV:L/AC:L/PR:L/UI:N/S:U/C:H/I:N/A:N/E:U/RL:O/RC:C
Vulnerability timeline
Timeline events are normalized from CVE metadata, CNA source timelines, ADP timelines, and KEV metadata when present.
- CVE reservedCVE Program
The CVE ID was reserved by the assigning CNA.
- CVE publishedCVE Program
The CVE record was published.
- CVE updatedCVE Program
The CVE record metadata indicates this as the latest update time.
ADP provider summaries
Source materials
- CVE List V5 sourceCVE List V5
- Windows WLAN AutoConfig Service Information Disclosure VulnerabilityCVE reference, microsoft · 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.
Out-of-bounds Read
Out-of-bounds Read represents a recurring weakness pattern that can create exploitable paths when design, validation, or implementation controls are missing.