How to Fix CVE-2026-23664: Azure IoT Explorer Information Disclosure in Azure IoT Explorer
Related fixes
Other vulnerabilities in the same area that are worth patching alongside this one:
- How to Fix CVE-2026-32171: Cwe-522: insufficiently protected credentials in Azure Logic Apps — Cwe-522: insufficiently protected credentials in Azure Logic Apps
- How to Fix CVE-2026-32151: Information disclosure in Microsoft Windows — Information disclosure in Microsoft Windows
- How to Fix CVE-2026-33841: Path Traversal in Windows 10 Version 21H2 , Path Traversal in Windows 10 Version 21H2
- How to Fix CVE-2026-27913: Improper input validation in Microsoft Windows Server , Improper input validation in Microsoft Windows Server
- How to Fix CVE-2026-25176: CWE-284: Improper Access Control in Windows 10 Version 1607 , CWE-284: Improper Access Control in Windows 10 Version 1607
*By Sai Kiran Pandrala*
| Severity | CVSS 7.5, High |
|---|---|
| Actively exploited? | No |
| Affected | Microsoft Azure IoT Explorer (1.0.0 < 0.15.13) |
| Fixed in | 0.15.13 |
| Type (CWE) | CWE-923: Improper Restriction of Communication Channel to Intended Endpoints |
What is CVE-2026-23664?
Improper restriction of communication channel to intended endpoints in Azure IoT Explorer allows an unauthorized attacker to disclose information over a network.
In practical terms, a successful attacker gets disclosure of sensitive information. There is no confirmed in-the-wild exploitation listed in CISA's KEV catalog at the time of writing, but the CVSS rating still warrants prompt patching.
Am I affected?
You're affected if you run Microsoft Azure IoT Explorer at any version in the Affected row above. Use these probes to find your installed build:
[System.Environment]::OSVersion.Version
Get-HotFix | Sort-Object InstalledOn -Descending | Select-Object -First 10
How to fix CVE-2026-23664
The primary fix is to upgrade to the patched build listed in the Fixed in row above (0.15.13). Pick the platform that matches your install and run the commands below.
Linux (Ubuntu / Debian)
sudo apt-get update
sudo apt-get install --only-upgrade azure-iot-explorer
# Confirm the installed version meets or exceeds 0.15.13
dpkg -s azure-iot-explorer | grep ^Version
Linux (RHEL / CentOS / Rocky)
sudo dnf upgrade --security azure-iot-explorer -y
rpm -q azure-iot-explorer
Windows (PowerShell, admin)
# Try winget first
winget upgrade --id 'Microsoft.Azure IoT Explorer' --silent --accept-source-agreements --accept-package-agreements
# If winget does not know the product, download the patched installer from the vendor and:
Start-Process -FilePath "$env:TEMP\AzureIoTExplorer-0.15.13.msi" -ArgumentList '/qn /norestart' -Wait
PowerShell script (Windows) - detect, back up, upgrade, verify, log
# Run as Administrator
$ErrorActionPreference = 'Stop'
$log = "$env:ProgramData\AzureIoTExplorer-Patch-CVE-2026-23664.log"
function Write-Log($msg) { "$(Get-Date -Format s) $msg" | Tee-Object -FilePath $log -Append }
Write-Log "Starting CVE-2026-23664 remediation for Microsoft Azure IoT Explorer"
# 1. Detect: replace the path/version probe with one valid for your install
$installed = (Get-WmiObject -Class Win32_Product |
Where-Object { $_.Name -like '*Azure*' } |
Select-Object -First 1 -ExpandProperty Version)
Write-Log "Detected version: $installed"
if (-not $installed) {
Write-Log "Product not installed on this host; nothing to do."
return
}
if ([version]$installed -ge [version]'0.15.13') {
Write-Log "Already at fixed version $installed; no action needed."
return
}
# 2. Backup configuration to a timestamped folder
$backup = "$env:ProgramData\AzureIoTExplorer-Backup-$(Get-Date -Format yyyyMMdd-HHmm)"
New-Item -ItemType Directory -Path $backup -Force | Out-Null
# Adjust the source path to match your install
$src = "$env:ProgramFiles\Microsoft\Azure IoT Explorer"
if (Test-Path $src) { Copy-Item -Path $src -Destination $backup -Recurse -Force }
Write-Log "Backed up config to $backup"
# 3. Apply the patched installer (place the verified file on a share or staging path)
$installer = "$env:TEMP\AzureIoTExplorer-0.15.13.msi"
if (-not (Test-Path $installer)) {
throw "Patched installer not found at $installer. Stage it from your software repo first."
}
Start-Process msiexec.exe -ArgumentList "/i `"$installer`" /qn /norestart" -Wait
Write-Log "Installer finished"
# 4. Verify
$verify = (Get-WmiObject -Class Win32_Product |
Where-Object { $_.Name -like '*Azure*' } |
Select-Object -First 1 -ExpandProperty Version)
if ([version]$verify -ge [version]'0.15.13') {
Write-Log "SUCCESS: now at $verify (>= 0.15.13)"
} else {
Write-Log "FAILURE: still at $verify after install"
exit 1
}
Bash script (Linux) - detect, back up, upgrade, verify, log
#!/usr/bin/env bash
set -euo pipefail
LOG=/var/log/azure-iot-explorer-patch-cve-2026-23664.log
log() { echo "$(date -Iseconds) $*" | tee -a "$LOG"; }
log "Starting CVE-2026-23664 remediation for Microsoft Azure IoT Explorer"
# 1. Detect installed version (works for deb and rpm packages)
if command -v dpkg >/dev/null && dpkg -s azure-iot-explorer >/dev/null 2>&1; then
CURRENT=$(dpkg-query -W -f='${Version}' azure-iot-explorer)
PKG_MGR=apt
elif command -v rpm >/dev/null && rpm -q azure-iot-explorer >/dev/null 2>&1; then
CURRENT=$(rpm -q --queryformat '%{VERSION}' azure-iot-explorer)
PKG_MGR=dnf
else
log "azure-iot-explorer not installed via apt or rpm; check your package manager or vendor instructions."
exit 0
fi
log "Detected: azure-iot-explorer=$CURRENT (manager=$PKG_MGR)"
# 2. Backup config
BACKUP=/var/backups/azure-iot-explorer-$(date +%Y%m%d-%H%M)
mkdir -p "$BACKUP"
for d in /etc/azure-iot-explorer /etc/${pkg%%-*} ; do
[ -d "$d" ] && cp -a "$d" "$BACKUP/" && log "Backed up $d to $BACKUP"
done
# 3. Upgrade
if [ "$PKG_MGR" = apt ]; then
sudo apt-get update -y
sudo apt-get install --only-upgrade -y azure-iot-explorer
else
sudo dnf upgrade --security -y azure-iot-explorer
fi
# 4. Verify
if [ "$PKG_MGR" = apt ]; then
NEW=$(dpkg-query -W -f='${Version}' azure-iot-explorer)
else
NEW=$(rpm -q --queryformat '%{VERSION}' azure-iot-explorer)
fi
log "After upgrade: $NEW"
# Optionally compare against 0.15.13 with dpkg --compare-versions or sort -V
log "Done. Restart the affected service if the package install did not."
If you can't patch immediately
These are runnable hardening commands. They reduce blast radius but they're not a replacement for the vendor patch.
No official vendor workaround is published for this CVE; patching is the only documented fix. The runnable hardening below is generic defense in depth, not a substitute for the patch.
Restrict the affected service to trusted networks (Linux):
# Vendor advisory: https://msrc.microsoft.com/update-guide/vulnerability/CVE-2026-23664
# Replace <port> with the affected service port and 10.0.0.0/24 with your admin subnet
sudo iptables -A INPUT -p tcp --dport <port> -s 10.0.0.0/24 -j ACCEPT
sudo iptables -A INPUT -p tcp --dport <port> -j DROP
Windows Firewall equivalent:
# Vendor advisory: https://msrc.microsoft.com/update-guide/vulnerability/CVE-2026-23664
New-NetFirewallRule -DisplayName 'Allow affected service from admin subnet' \
-Direction Inbound -Action Allow -Protocol TCP -LocalPort <port> -RemoteAddress 10.0.0.0/24
New-NetFirewallRule -DisplayName 'Block affected service from everywhere else' \
-Direction Inbound -Action Block -Protocol TCP -LocalPort <port>
How to verify the fix worked
Run the version probe again and confirm the running build matches the Fixed in row above.
Get-HotFix | Sort-Object InstalledOn -Descending | Select-Object -First 5
Expected output: the KB ID listed in the vendor advisory appears with an InstalledOn date that matches your patch window.
Then re-run any vulnerability scanner you used previously and confirm the finding for CVE-2026-23664 has cleared. Sweep your logs for the indicators of compromise listed in the vendor or CISA advisory, especially if the system was internet-reachable during the disclosure window.
Frequently asked questions
Is CVE-2026-23664 being actively exploited?
Not at the time of writing. It is not listed in CISA's Known Exploited Vulnerabilities catalog. That status can change, so monitor the vendor advisory and the KEV catalog if the system is exposed.
How severe is CVE-2026-23664?
CVSS rates it 7.5 (High). Use that score to set your patch priority next to the other items in your queue.
Do I have to take Azure IoT Explorer offline to apply the patch?
It depends on the deployment. High-availability or clustered installs can usually patch one node at a time with no full outage. Standalone installs typically need a short restart. Always follow the vendor's documented upgrade steps.
What if my vulnerability scanner still flags CVE-2026-23664 after I patch?
Re-run the scan after a service restart, then confirm the scanner's plugin set is up to date. Some scanners detect by banner version only and lag the official fix metadata by a release.
References
- Official vendor advisory: https://msrc.microsoft.com/update-guide/vulnerability/CVE-2026-23664
- NVD: https://nvd.nist.gov/vuln/detail/CVE-2026-23664
- CISA KEV catalog: https://www.cisa.gov/known-exploited-vulnerabilities-catalog
*Written by Sai Kiran Pandrala on 2026-05-25. Sourced from the official vendor advisory, the NVD record, and the CISA KEV listing. Always confirm against the vendor advisory before applying changes in production.*