CVE-2026-45639
Official description Straight from the sourceThe vendor's or NVD's own wording, published unedited. Authoritative, but often terse — it says what broke, rarely what to do.
NVD · uneditedOut-of-bounds read in Windows RDP allows an unauthorized attacker to disclose information over a network.
Technical summary Written by usOur analysis, written from the advisory, the CVSS vector and the affected-version data. It adds context the advisory leaves out, and never invents facts that are not in the source.
dbcve analysis · high confidenceThis is an out-of-bounds read vulnerability in Windows Remote Desktop Protocol (RDP). An unauthenticated attacker on the network can exploit this to read memory contents beyond intended bounds, potentially disclosing sensitive information from the affected system's memory.
Verify against the referenced sources before acting — the references below are authoritative for this CVE, this summary is not.
Affected products & versions What the vendor confirmedThe version ranges the vendor confirmed as vulnerable. If your version sits inside a range here, treat yourself as exposed until you have upgraded.
NVD · CPE data< 1.2.7214< 2.0.1193.0< 10.0.14393.9234< 10.0.17763.8880< 10.0.19044.7417< 10.0.19045.7417< 10.0.22631.7219< 10.0.26100.8655CVSS breakdown How the score is builtThe industry scoring standard. It rates how the flaw is reached, what it takes to exploit, and what an attacker gains — the score is derived from those, not the other way round.
From the vector- Attack vector
- Network
- Complexity
- Low
- Privileges
- None
- User interaction
- None
- Scope
- Unchanged
- Confidentiality
- High
- Integrity
- None
- Availability
- None
CVSS:3.1/AV:N/AC:L/PR:N/UI:N/S:U/C:H/I:N/A:N
Am I affected? How to checkSteps we derive from the advisory and the affected-version data, so you can decide whether this CVE reaches your setup. They are a guide, not a scan — your own configuration is the authority.
dbcve checksWork through these to decide whether this CVE applies to you.
-
Check Windows version against affected buildsRun 'winver' or 'systeminfo | findstr /B /C:"OS Name" /C:"OS Version"' and compare the build number to the affected ranges (10.0.14393.9234 and below for 1607; 10.0.17763.8880 and below for 1809; 10.0.19044.7417 and below for 21h2; 10.0.19045.7417 and below for 22h2; 10.0.22631.7219 and below for 23h2; 10.0.26100.8655 and below for 24h2).Affected if The installed Windows build number is lower than any of the affected thresholds for your Windows release.
-
Check if RDP is enabled on the systemRun 'Get-ItemProperty -Path 'HK:\System\CurrentControlSet\Control\Terminal Server' -Name 'fDenyTSConnections' | Select-Object fDenyTSConnections' in PowerShell. A value of 0 means RDP is enabled.Affected if RDP is enabled (fDenyTSConnections = 0) on an affected Windows version.
-
Check Remote Desktop Client versionCheck the mstsc.exe version by right-clicking mstsc.exe in C:\Windows\System32, selecting Properties, and viewing the Details tab, or run 'Get-ItemProperty C:\Windows\System32\mstsc.exe | Select-Object VersionInfo'.Affected if The client version is earlier than 1.2.7214.
-
Check Microsoft Windows App versionOpen the Microsoft Store, go to Library, find Microsoft Windows App, and check the version, or run 'Get-AppxPackage *Microsoft.WindowsApp* | Select-Object Name, Version'.Affected if The Microsoft Windows App version is earlier than 2.0.1193.0.
-
Verify RDP port is listeningRun 'netstat -an | findstr ':3389' or check firewall rules with 'Get-NetFirewallRule -DisplayName "Remote Desktop*" | Select-Object Name, Enabled'.Affected if Port 3389 is listening or RDP firewall rules are enabled on an affected version.
Your system is likely affected if it runs an affected Windows version or RDP client version AND has RDP functionality exposed or enabled.
Generated from the published advisory. Verify against your own configuration.
Remediation Closing itWhat it takes to close this. Where a vendor fix exists we point at it; where none exists we say so plainly, and can build one. Effort estimates are scoped from the advisory, not from your codebase.
dbcve · scoped1.2.72142.0.1193.010.0.14393.9234
Apply the relevant Microsoft security update for this RDP vulnerability. If immediate patching is not possible, restrict network access to RDP ports (3389) via firewall rules or disable RDP if not required.
Upgrade to Windows 10 1607 build >=10.0.14393.9234, Windows 10 1809 build >=10.0.17763.8880, Windows 10 21h2 build >=10.0.19044.7417, Windows 10 22h2 build >=10.0.19045.7417, Windows 11 23h2 build >=10.0.22631.7219, Windows 11 24h2 build >=10.0.26100.8655, Windows App >=2.0.1193.0, or Remote Desktop
- Identify the exact Windows version and build number by running 'winver' or 'systeminfo'
- Identify the Remote Desktop Client version by checking About in the RDP client or reviewing installed programs
- For Windows 10 1607: Install security update to reach build 10.0.14393.9234 or later
- For Windows 10 1809: Install security update to reach build 10.0.17763.8880 or later
- For Windows 10 21h2: Install security update to reach build 10.0.19044.7417 or later
- For Windows 10 22h2: Install security update to reach build 10.0.19045.7417 or later
- For Windows 11 23h2: Install security update to reach build 10.0.22631.7219 or later
- For Windows 11 24h2: Install security update to reach build 10.0.26100.8655 or later
Generated from the published advisory — verify against the referenced sources before acting.
- Consultation2.0 h
- Implementation4.0 h
- Testing2.0 h
- Review / QA1.0 h
An estimate, not a bill — we confirm scope with you before any work starts. Need it this week? Rush from $2,560.
Scan for this in your stack
Free · runs locallyCheck whether your project pulls in CVE-2026-45639 — or any other known-vulnerable package — straight from your lock files. Free and open source; it runs locally and uploads nothing.
References Go to the primary sourcePrimary sources — vendor advisories, patches and trackers. Where our summary and a reference disagree, the reference wins.
Primary sourcesPractitioner notes
ContributedPeer-ranked notes from engineers who’ve handled CVE-2026-45639 in production — separate from our analysis above.
The advisory tells you what broke. It rarely tells you what actually worked. If you’ve dealt with this one, that detail is what the next engineer is searching for.
- The version that genuinely resolved it — not the one the vendor claimed
- A config change or rule that shut the vector down
- A gotcha in the upgrade path that cost you an afternoon
No notes yet
Be the first to add a field note for this CVE — a mitigation you’ve verified, a version caveat, or a link to a working fix. Sign in above to contribute.
A place for practitioners to share what actually worked: a mitigation you’ve tested, a configuration change, a version- or environment-specific caveat, or a link to a verified patch. The most useful notes rise to the top as peers upvote them, so the signal stays high.
- Verified mitigations, workarounds, and config changes
- Version or environment caveats, and links to real fixes
- No weaponised exploit code, or anything meant to cause harm
- No spam, self-promotion, credentials, or personal data