CVE-2017-9248VulnerabilityPublished 11/03/2021Updated 10/24/2026

CVE-2017-9248: Progress Telerik UI for ASP.NET AJAX and Sitefinity Cryptographic Weakness Vulnerability

Affects Progress ASP.NET AJAX and SitefinitySource CISA KEV

Severity

High

No CVSS score published yet

Exploitation: Actively exploited – in CISA KEV since 11/03/2021
KEV deadline: 05/03/2022
EPSS: 75.1% chance of exploitation in 30 days – higher than 99% of CVEs

What to do

CISA required action

Apply updates per vendor instructions.

nvd.nist.gov/vuln/detail/CVE-2017-9248 (opens in a new tab)

Description

CVE-2017-9248 is a cryptographic weakness in Progress Telerik UI for ASP.NET AJAX and Sitefinity's Telerik.Web.UI.dll. This vulnerability can lead to disclosure of encryption keys, enable cross-site scripting (XSS) attacks, compromise ASP.NET ViewState integrity, and allow unauthorized file upload and download. It has been exploited in the wild and is considered a high-severity issue.

Summary

The vulnerability CVE-2017-9248 affects Progress Telerik UI for ASP.NET AJAX and Sitefinity products due to a cryptographic weakness in the Telerik.Web.UI.dll component. This weakness can be exploited to disclose sensitive encryption keys such as Telerik.Web.UI.DialogParametersEncryptionKey and/or the MachineKey. Exploitation can result in cross-site scripting (XSS) attacks, compromise of the ASP.NET ViewState mechanism, and unauthorized file upload and download capabilities. The vulnerability has been observed in active exploitation scenarios.

Impact

Exploitation of this vulnerability can lead to disclosure of sensitive cryptographic keys, enabling attackers to bypass security controls. This can facilitate cross-site scripting attacks, compromise the integrity of ASP.NET ViewState data, and allow unauthorized file operations, potentially leading to further system compromise. The vulnerability has been exploited in the wild, indicating active threat to affected systems.

Mitigation

No specific patch or remediation details are provided in the available data. Patch status is not yet confirmed — check the vendor advisory for current remediation guidance. Until an official fix is available, organizations should monitor vendor communications and apply any recommended mitigations promptly.

Weaknesses

CWE-522Insufficiently Protected Credentials (opens in a new tab)

What to do

Description

AnalysisAI-generated, updated 10/24/2026, 08:55:20 UTC

Weaknesses

References

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