cbcvebase.
CVE-2021-42310
published 2021-12-15

CVE-2021-42310: Microsoft Defender for IoT Remote Code Execution Vulnerability

PriorityP260critical9.8CVSS 3.1
AVNACLPRNUINSUCHIHAH
EPSS
1.99%
78.3th 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/IotDefenderSigningCertificate.pem
path/var/cyberx/reset_password/ResetPassword.json
port9090
commandopenssl enc -d -aes256 -in ./product.tar.gz -md sha512 -k | tar xz -C
  • 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.
  • The vulnerability exploits the password recovery flow: an attacker uploads a crafted ZIP to the reset_password path, then triggers PasswordRecoveryApiHandler via POST. Even if certificate validation fails, the internal Tomcat reset-password endpoint is still called and a new password is generated and returned. Detect unauthenticated POST requests to the password recovery API endpoint.
  • Monitor for unexpected changes to the 'cyberx' or 'support' user passwords on Defender for IoT appliances, which may indicate exploitation of the password recovery bypass.
  • ·The decryption key for the product.tar.gz archive is shared across all Defender for IoT installations, meaning any attacker who obtains it can decrypt the source code from any installation.
  • ·Both the Management and Sensor components share roughly the same code base, meaning both are affected by the same vulnerabilities including CVE-2021-42310.
  • ·The same web interface credentials are also used as SSH login credentials, meaning a successful password reset via this vulnerability also grants SSH access.
  • ·The fix requires upgrading to Microsoft Defender for IoT version 10.5.2 or above.

CVSS provenance

nvdv3.19.8CRITICALCVSS:3.1/AV:N/AC:L/PR:N/UI:N/S:U/C:H/I:H/A:H
nvdv2.07.5HIGHAV:N/AC:L/Au:N/C:P/I:P/A:P
vendor_msrc8.1HIGH
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