Security readout for executives and security teams
Plain-English summary
A memory-safety flaw in the Windows LDAP client could let an unauthenticated network attacker run code on an affected computer. Successful exploitation could compromise confidentiality, integrity, and availability. Exploitation is rated high complexity, so attacks may require specific conditions, but no user interaction or prior privileges are identified.
Executive priority
Treat this as a high-priority patching item, especially for servers or identity-connected systems using affected Windows releases. Its potential impact is full code execution without authentication or user action. However, the available evidence does not show active exploitation, and successful attacks are assessed as high complexity.
Technical view
CVE-2025-26670 is a use-after-free vulnerability (CWE-416) in Windows LDAP client functionality. It carries CVSS 3.1 score 8.1: network-accessible, high complexity, no privileges or user interaction, unchanged scope, and high impact across confidentiality, integrity, and availability. The supplied sources do not describe the triggering sequence or execution context.
Likely exposure
Exposure applies to the listed Windows 10, Windows 11, and Windows Server releases, including specified Server Core installations. Systems using affected LDAP client functionality with attacker-influenced network interactions warrant priority. The bundle does not establish which applications invoke the vulnerable component or whether ordinary LDAP server exposure alone is sufficient.
Exploitation context
The bundle reports no CISA KEV listing, and the CVSS vector marks exploit maturity as unproven. Therefore, active exploitation is not established. Network access, no authentication, and no user interaction increase concern, while high attack complexity may limit reliability or require conditions not disclosed in the supplied sources.
Researcher notes
The public bundle identifies the weakness class and CVSS characteristics but omits trigger details, affected process context, and attack prerequisites. Avoid assuming that exposed LDAP services are automatically vulnerable because this issue is identified in the client. Validate affected builds and update applicability directly against Microsoft’s advisory.
Mitigation direction
- Apply the applicable Microsoft security update identified by the MSRC advisory.
- Check Microsoft guidance for each Windows release and installation type in your inventory.
- Prioritize affected servers and systems performing LDAP-dependent business or identity functions.
- Use compensating network controls where updates cannot be applied promptly, following vendor guidance.
Validation and detection
- Inventory operating-system versions and compare them with the affected releases in the source bundle.
- Confirm the applicable Microsoft security update is installed on each affected system.
- Review vulnerability-scanner results after updating and investigate systems still reported vulnerable.
- Test critical LDAP-dependent applications after remediation to confirm normal operation.
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 lookupExecution behavior lookup
The CVE wording references code or command execution, so execution technique review may help defensive triage. This is a Glexia inferred lookup path, not an official MITRE, ATT&CK, or CVE Program mapping.
Open ATT&CK lookupCVE-2025-26670 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
- 8.1 (3.1)
- Known Exploited
- No
- Published
Vector: CVSS:3.1/AV:N/AC:H/PR:N/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.
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:N/AC:H/PR:N/UI:N/S:U/C:H/I:H/A:H/E:U/RL:O/RC:C2.25.9microsoftVulnerability scoring details
Base CVSS 3.1 score
8.1HighVector: CVSS:3.1/AV:N/AC:H/PR:N/UI:N/S:U/C:H/I:H/A:H/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
- Lightweight Directory Access Protocol (LDAP) Client Remote Code Execution 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.
Use After Free
Use After Free represents a recurring weakness pattern that can create exploitable paths when design, validation, or implementation controls are missing.