# CVE-2026-121678: Microsoft Remote Desktop Client out-of-bounds read

Source: https://junglewise.ai/threats/cve-2026-121678-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-2026-121678 · Severity: medium · CVSS 5.3 · Published 2026-11-10

Microsoft Remote Desktop Client, used to access remote computers, contains a flaw that allows an attacker to read sensitive information from memory over the network without authentication. An attacker exploiting this vulnerability could disclose confidential data such as credentials, session tokens, or other sensitive information stored in the application's memory.

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-2026-121678 exploited in the wild?** No. Junglewise Threat Intelligence has no report of CVE-2026-121678 being exploited in the wild.

**How severe is CVE-2026-121678?** Medium severity, with a CVSS score of 5.3, published 10 November 2026.

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

**Is there a fix for CVE-2026-121678?** 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-2026-121678 attacked?** It is attacked over the network.

**Am I affected by CVE-2026-121678?** 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 vulnerability in the Remote Desktop Client allows an attacker to read memory beyond allocated buffer boundaries. The vulnerability can be exploited over the network without requiring authentication or user interaction, potentially exposing sensitive data from the client process memory.

## Affected products

- Microsoft Remote Desktop Client

## References

- [https://msrc.microsoft.com/update-guide/vulnerability/CVE-2026-121678](https://msrc.microsoft.com/update-guide/vulnerability/CVE-2026-121678)

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