CVE-2026-57098Network attack vector

Information disclosure via improper signature verification

Published Sep 8, 2026 · Updated Sep 9, 2026

Improper signature verification in Microsoft Remote Desktop client for Windows before 1.2.7279.0 allows remote attackers to disclose information. Microsoft identifies the Windows RDP Client's cryptographic-signature verification as faulty but has not disclosed the checked object, code locus, or acceptance error. Network reachability without authentication is sufficient; the published impact is limited to confidentiality, with no reported data modification or service interruption.

CVSS severity7.5
High
EPSS probability0.63%
Next 30 days · Sep 16, 2026
Known exploitationUnconfirmed
Based on sourced intelligence
Hinoki checkNot available
Coverage for this vulnerability

See if you're affected

Explore vulnerability checks for your environment with Hinoki.

Book a demo

Summary

What happened

Improper signature verification in Microsoft Remote Desktop client for Windows before 1.2.7279.0 allows remote attackers to disclose information. Microsoft identifies the Windows RDP Client's cryptographic-signature verification as faulty but has not disclosed the checked object, code locus, or acceptance error. Network reachability without authentication is sufficient; the published impact is limited to confidentiality, with no reported data modification or service interruption.

The record

CVE
CVE-2026-57098
Published
Sep 8, 2026
Updated
Sep 9, 2026
Vendor
Microsoft
Product
Remote Desktop client for Windows Desktop
Classifications
CWE-347
Attack vector
network
Privileges
unauthenticated

Timeline

How it unfolded

  1. Sep 8, 2026CVE publishedPublication date reported by the CVE source.
  2. Sep 9, 2026Record updatedLatest update available in the CVE record.

Exploitability

Present is not the same as exploitable

Compare your product and version with the public record. A matching version still requires validation against your environment.

Is a vulnerable build present?

Compare these published version ranges with your installed build and any vendor patches.

  1. Affected versionversion=1.2.0.0 <1.2.7279.0

What conditions does exploitation require?

Attack vectornetwork
Required privilegesunauthenticated

What is affected?

Microsoft · Remote Desktop client for Windows Desktopversion=1.2.0.0 <1.2.7279.0

Published CVSS scores

7.5MicrosoftCVSS:3.1/AV:N/AC:L/PR:N/UI:N/S:U/C:H/I:N/A:N

CVSS describes severity. EPSS estimates exploitation probability.

Attacks

What attackers are doing with it

Daily unique IPs observed by Shadowserver honeypots for known exploited vulnerabilities (KEVs). Missing observations do not establish an absence of attacks.

Daily unique IPsNo honeypot observations are available for this CVE in the selected window.

No observations available

Sep 9, 2026Sep 15, 2026
Latest reporting daySep 15, 2026
Latest daily unique IPsUnavailable
Prior 30-day averageUnavailable
SourceShadowserver honeypots (KEV)
Vectornetwork
Privilegesunauthenticated
Known exploitationUnconfirmed
Public exploitUnconfirmed

Weakness, pattern, technique

CWE-347Improper Verification of Cryptographic Signature

Public exploit references

No public exploit references are available in this record.

Labels summarize the accepted research assessment. They do not indicate a test against your environment.

Technologies

Your stack

See the directory against your own environment.

Your stack

Check the software in your environment

Book a demo to see how Hinoki identifies affected software and validates exploitability in your environment.

Book a demo