Telerik UI Flaws Let Attackers Chain AES

Gbhackers •Divya • September 7, 2026

Security researchers have identified a critical vulnerability chain in Progress Telerik UI for ASP.NET AJAX, which allows unauthenticated attackers to escalate from a cryptographic padding oracle to remote code execution on exposed web applications. Documented by Tanto Security researcher Marcio Almeida, this vulnerability affects Telerik UI for ASP.NET AJAX versions 2010.1.309 through 2026.2.519. To address […]

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Telerik UI Vulnerability Chain Enables Unauthenticated RCE Attacks A significant vulnerability chain in Telerik UI for ASP.NET AJAX has been disclosed, allowing unauthenticated attackers to achieve remote code execution (RCE) through a padding oracle exploit. The vulnerabilities affect versions 2010.1.309 to 2026.2.519, with a patch available in version 2026.2.708. The attack exploits a combination of an unauthenticated AES-CBC padding oracle and insecure deserialization in the RadAsyncUpload component. Researchers from Tanto Security demonstrated the exploit, releasing a proof-of-concept tool that includes payloads for executing commands on vulnerable servers. Progress Software has confirmed the vulnerabilities and released advisories, but there are no known instances of exploitation in the wild as of now. Users are urged to upgrade to the patched version to mitigate the risks. The vulnerabilities are tracked under CVEs including CVE-2026-13181 and CVE-2026-13182. 3 sources 58

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Platforms (1)

Progress Telerik UI For Asp.net AJAX