Progress Telerik UI for ASP.NET AJAX and Sitefinity Cryptographic Weakness Vulnerability (CVE-2017-9248)
Severity: critical · Patch status: patched · Since 2021-11-03 · CVE-2017-9248
Progress Telerik UI for ASP.NET AJAX and Sitefinity have a cryptographic weakness in Telerik.Web.UI.dll that can be exploited to disclose encryption keys (Telerik.Web.UI.DialogParametersEncryptionKey and/or the MachineKey), perform cross-site-scripting (XSS) attacks, compromise the ASP.NET ViewState, and/or upload and download files. CISA added CVE-2017-9248 to its Known Exploited Vulnerabilities catalog on Nov 3, 2021, which means attackers are exploiting it in the wild.
What to do
- Apply updates per vendor instructions.
- US federal agencies must remediate by May 3, 2022 (BOD 22-01); treat that as the outer limit.
Sources
All live incidents on Threat Watch