cbcvebase.
CVE-2021-42311
published 2021-12-15

CVE-2021-42311: Microsoft Defender for IoT Remote Code Execution Vulnerability

PriorityP261critical9.8CVSS 3.1
AVNACLPRNUINSUCHIHAH
ITW
Exploited in the wild
EPSS
4.03%
89.4th percentile
Microsoft Defender for IoT Remote Code Execution Vulnerability

Affected

3 ranges
VendorProductVersion rangeFixed in
microsoftdefender_for_iot< 10.5.210.5.2
microsoftmicrosoft_defender_for_iot>= 22.0.0 < 10.5.210.5.2
msrcmicrosoft_defender_for_iot

Detection & IOCsextracted from sources · hover to see the quote

urlhttp://127.0.0.1:9090/core/api/v1/login/reset-password
path/var/cyberx/reset_password
path/var/cyberx/reset_password/IotDefenderSigningCertificate.pem
path/var/cyberx/reset_password/ResetPassword.json
pathcomponents\xsense-web\cyberx_web\api\admin.py
filenameIotDefenderSigningCertificate.pem
filenameResetPassword.json
port9090
  • Monitor for unauthenticated POST requests to the ZipFileConfigurationApiHandler endpoint with path parameter set to 'reset_password', which triggers ZIP extraction to /var/cyberx/reset_password without authentication.
  • Detect exploitation attempts via SQL injection triggered through the password recovery mechanism; attacker extracts secrets from their own machine to craft the payload.
  • Alert on unauthenticated POST requests to the PasswordRecoveryApiHandler endpoint with user field set to 'cyberx' or 'support', especially when certificate validation fails but execution continues.
  • Monitor for ZIP file uploads to the Defender for IoT web interface that contain files named IotDefenderSigningCertificate.pem, issuer.pem, or ResetPassword.json from untrusted sources.
  • Monitor internal Tomcat service on port 9090 for unexpected inbound POST requests to /core/api/v1/login/reset-password, which may indicate exploitation of the password reset flow.
  • ·The decryption key for the product archive is shared across all Defender for IoT installations, meaning any attacker with access to one installation can decrypt the source on any other installation.
  • ·Both the management and sensor components share roughly the same code base, meaning both are affected by the same vulnerabilities.
  • ·The fix requires upgrading to version 10.5.2 or above; no in-the-wild exploitation had been observed at time of publication.

CVSS provenance

nvdv3.19.8CRITICALCVSS:3.1/AV:N/AC:L/PR:N/UI:N/S:U/C:H/I:H/A:H
nvdv2.010.0CRITICALAV:N/AC:L/Au:N/C:C/I:C/A:C
vendor_msrc10.0CRITICAL
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