# CVE-2026-58637: Microsoft Windows Client-Side Caching Service privilege escalation

Source: https://junglewise.ai/threats/cve-2026-58637-microsoft-windows-client-side-caching-service-privilege  
Publisher: Junglewise Threat Intelligence, https://junglewise.ai/threats  
Published: 2026-07-14. Updated: 2026-07-14  
License: CC BY 4.0 with a link back

CVE-2026-58637 · Severity: high · CVSS 7 · Published 2026-07-14

A security vulnerability exists in the Windows Client-Side Caching (CSC) Service, which manages offline access to network files. An attacker who already has basic access to a computer could exploit this flaw to gain full administrative control over the system. This could allow them to view sensitive data, install malicious software, or disrupt business operations.

Technologies: [Microsoft Windows 11](https://junglewise.ai/threats/technologies/windows-11), [Microsoft Windows 10](https://junglewise.ai/threats/technologies/windows-10), [Microsoft Windows Server 2012](https://junglewise.ai/threats/technologies/windows-server-2012). Vendors: [Microsoft](https://junglewise.ai/threats/vendors/microsoft).

## Quick answers

**Is CVE-2026-58637 exploited in the wild?** No. Junglewise Threat Intelligence has no report of CVE-2026-58637 being exploited in the wild.

**How severe is CVE-2026-58637?** High severity, with a CVSS score of 7, published 14 July 2026.

**Which products and versions are affected?** Microsoft Windows 11 24H2, 25H2, 26H1; Microsoft Windows 10 1607, 1809, 21H2, 22H2; Microsoft Windows Server 2012 All editions.

**Is there a fix for CVE-2026-58637?** No fixed version is recorded yet. Check the vendor's advisory in the references below. If you run it, Junglewise drafts a mitigation that fits your setup and applies it once you approve, with senior security engineers behind it.

**How is CVE-2026-58637 attacked?** It is attacked with local access, in an operating system.

**Am I affected by CVE-2026-58637?** Check whether you run Microsoft Windows 11, Microsoft Windows 10 or Microsoft Windows Server 2012 at an affected version. Junglewise does that check for you around the clock: connect your code, cloud and domains, and it matches new vulnerabilities like this one against what you actually run and tells you when one reaches you.

## Technical details

A use-after-free (CWE-416) vulnerability exists within the Windows Client-Side Caching (CSC) Service. The flaw is triggered when the service incorrectly manages memory objects during file caching operations, allowing an attacker to reuse a memory pointer after it has been freed. To exploit this, an attacker must have local access to the target system and execute a specially crafted application. Successful exploitation enables the attacker to gain SYSTEM privileges. Microsoft has released security updates to address this issue across affected Windows and Windows Server versions.

## Affected products

- Microsoft Windows 10 1607, 1809, 21H2, 22H2
- Microsoft Windows 11 24H2, 25H2, 26H1
- Microsoft Windows Server 2012 All editions

## Timeline

- 2026-07-14: advisory
- 2026-07-14: disclosed

## References

- [https://msrc.microsoft.com/update-guide/vulnerability/CVE-2026-58637](https://msrc.microsoft.com/update-guide/vulnerability/CVE-2026-58637)

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