Telerik UI Padding-Oracle Bug Chained to Unauthenticated RCE — Public Exploit Released
TantoSec published a working exploit chaining a Telerik UI padding oracle to unauthenticated RCE; Progress patched the flaws in July.
TantoSec's Marcio Almeida released a full exploit chain and tooling for the RadAsyncUpload control in Telerik UI for ASP.NET AJAX, turning a padding oracle (CVE-2026-13182) into unauthenticated RCE via an unguarded type-resolution flaw (CVE-2026-13181, CVSS 8.1). Exploitation requires a rendered RadAsyncUpload handler and an explicit non-default encryption key, and took roughly 127,000 oracle requests (about an hour) in lab testing. Versions 2010.1.309 through 2026.2.519 are affected; Progress fixed the chain in 2026.2.708 on July 8, 2026, and no in-the-wild exploitation has been confirmed. A separate RCE chain in RadPersistenceManager and RadDockLayout (CVE-2026-13185, -13186, -13190) was also patched but has no public exploit.