# CVE-2026-121677: Microsoft Remote Desktop Client out-of-bounds read

Source: https://junglewise.ai/threats/cve-2026-121677-out-of-bounds-read-in-remote-desktop-client-allows-an  
Publisher: Junglewise Threat Intelligence, https://junglewise.ai/threats  
Published: 2026-11-10. Updated: 2026-11-10  
License: CC BY 4.0 with a link back

CVE-2026-121677 · Severity: medium · CVSS 6.5 · Published 2026-11-10

Microsoft Remote Desktop Client contains an out-of-bounds read vulnerability that allows an attacker on the network to read sensitive information from memory without authentication. An attacker could exploit this to disclose credentials, session data, or other confidential information transmitted over the remote desktop connection.

Technologies: [Microsoft Remote Desktop Client](https://junglewise.ai/threats/technologies/remote-desktop-client). Vendors: [Microsoft](https://junglewise.ai/threats/vendors/microsoft).

## Quick answers

**Is CVE-2026-121677 exploited in the wild?** No. Junglewise Threat Intelligence has no report of CVE-2026-121677 being exploited in the wild.

**How severe is CVE-2026-121677?** Medium severity, with a CVSS score of 6.5, published 10 November 2026.

**Which products and versions are affected?** Microsoft Remote Desktop Client.

**Is there a fix for CVE-2026-121677?** 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-2026-121677 attacked?** It is attacked over the network, in a hosted service.

**Am I affected by CVE-2026-121677?** Check whether you run Microsoft Remote Desktop Client. 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

An out-of-bounds read flaw in the Remote Desktop Client allows an unauthenticated network attacker to access memory outside allocated bounds. The vulnerability requires network access to the Remote Desktop service and permits information disclosure; no remote code execution is indicated.

## Affected products

- Microsoft Remote Desktop Client

## Timeline

- 2026-11-10: disclosed

## References

- [https://msrc.microsoft.com/update-guide/vulnerability/CVE-2026-121677](https://msrc.microsoft.com/update-guide/vulnerability/CVE-2026-121677)

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