Description
In Progress® Telerik® UI for AJAX prior to v2026.2.708, when Telerik.Upload.ConfigurationHashKey is absent and machineKey is not explicitly configured, upload metadata integrity protection may fall back to a predictable default key, enabling attackers to forge protected upload metadata and unlock further exploit chains.
Affected products
progress: telerik ui for asp.net ajax
References1
- www.telerik.com/products/aspnet-ajax/documentation/knowledge-ba… Vendor AdvisoryMitigation
Metrics
- CVSS 3.1
-
7.5
HIGH
Score source: CNA
CVSS:3.1/AV:N/AC:L/PR:N/UI:N/S:U/C:N/I:H/A:N - EPSS — exploit probability
- 0% percentile: 24 · as of 14 November 2026
- CWE
- CWE-321
Could this be exploited in your environment?
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