Vulnerability Note VU#838200

Telerik Web UI contains cryptographic weakness

Original Release date: 25 Jul 2017 | Last revised: 25 Jul 2017


The Telerik Web UI, versions R2 2017 (2017.2.503) and prior, is vulnerable to a cryptographic weakness which an attacker can exploit to extract encryption keys.


CWE-326: Inadequate Encryption Strength - CVE-2017-9248

The Telerik.Web.UI.dll is vulnerable to a cryptographic weakness which allows the attacker to extract the Telerik.Web.UI.DialogParametersEncryptionKey and/or the MachineKey.
Versions R2 2017 (2017.2.503) and prior are vulnerable.


A remote, unauthenticated attacker could perform arbitrary file upload and downloads, cross-site scripting attacks, leak the MachineKey, or compromise the ASP.NET ViewState.
Software vendors who use Telerik web components may also be impacted.


Apply an update
Please see the Telerik's support article for update information for specific versions.

The support article also provides information to those who are unable to update their software.

Vendor Information (Learn More)

VendorStatusDate NotifiedDate Updated
DotNetNukeAffected-18 Jul 2017
TelerikAffected-19 Jul 2017
If you are a vendor and your product is affected, let us know.

CVSS Metrics (Learn More)

Group Score Vector
Base 7.5 AV:N/AC:L/Au:N/C:P/I:P/A:P
Temporal 7.5 E:ND/RL:ND/RC:ND
Environmental 5.6 CDP:ND/TD:M/CR:ND/IR:ND/AR:ND



Telerik thanks to Erlend Leiknes, security consultant in Mnemonic AS, and Thanh Van Tien Nguyen for reporting this vulnerability.

This document was written by Trent Novelly.

Other Information

  • CVE IDs: CVE-2017-9248
  • Date Public: 26 Jun 2017
  • Date First Published: 25 Jul 2017
  • Date Last Updated: 25 Jul 2017
  • Document Revision: 11


If you have feedback, comments, or additional information about this vulnerability, please send us email.