Vulnerabilities

In Progress Telerik UI for WPF versions prior to 2024 Q4 (2024.4.1213), a code execution attack is possible through an insecure deserialization vulnerability.

In Progress Telerik UI for WPF versions prior to 2024 Q4 (2024.4.1111), a code execution attack is possible through an insecure deserialization vulnerability.

In Progress Telerik UI for WPF versions prior to 2024 Q3 (2024.3.924), a command injection attack is possible through improper neutralization of hyperlink elements.

CVE-2024-4358 is a critical (CVSS 9.8) authentication bypass by spoofing (CWE-290) in Progress Telerik Report Server 2024 Q1 (10.0.24.305) and earlier when the server is deployed on IIS. The flaw is reachable over the network with no privileges and no user interaction, so a remote, unauthenticated attacker can spoof a valid session to reach Report Server functionality that should require sign-in; public reporting indicates this can be abused to create rogue administrator accounts and take over the instance. Access to restricted functionality and administrative control is the immediate gain, and per a released public proof of concept the bypass can be chained with the CVE-2024-1800 deserialization flaw to achieve unauthenticated remote code execution. Any organization running Telerik Report Server 2024 Q1 or earlier on IIS is affected. Exploitation is confirmed in the wild: CISA added the bug to the KEV catalog on 2024-06-13, and the 97.5% EPSS score (100th percentile) signals a very high likelihood of continued exploitation, though ransomware use is listed as unknown.

Do: Upgrade every Telerik Report Server instance to Progress' fixed release (2024 Q2, 10.0.24.414, or later per the vendor advisory); if prompt patching is not possible, CISA's required action is to apply vendor mitigations or discontinue use of the product. Audit the Users/Administrators list for rogue admin accounts, review IIS logs for unauthenticated requests to restricted endpoints, and inventory for any instances hosted on IIS. If your deployment is also exposed to CVE-2024-1800, patch that as well, since the public PoC chains the two flaws for unauthenticated RCE.

Telerik Fiddler through 5.0.20202.18177 allows attackers to execute arbitrary programs via a hostname with a trailing space character, followed by --utility-and-browser --utility-cmd-prefix= and the pathname of a locally installed program. The victim must interactively choose the Open On Browser option. Fixed in version 5.0.20204.

An issue was discovered in Progress Telerik UI for Silverlight before 2020.1.330. The RadUploadHandler class in RadUpload for Silverlight expects a web request that provides the file location of the uploading file along with a few other parameters. The uploading file location should be inside the directory where the upload handler class is defined. Before 2020.1.330, a crafted web request could result in uploads to arbitrary locations.

Path traversal in RadChart in Telerik UI for ASP.NET AJAX allows a remote attacker to read and delete an image with extension .BMP, .EXIF, .GIF, .ICON, .JPEG, .PNG, .TIFF, or .WMF on the server through a specially crafted request. NOTE: RadChart was discontinued in 2014 in favor of RadHtmlChart. All RadChart versions were affected. To avoid this vulnerability, you must remove RadChart's HTTP handler from a web.config (its type is Telerik.Web.UI.ChartHttpHandler).

CVE-2019-18935 is a .NET deserialization flaw (CWE-502) in the RadAsyncUpload function of Progress Telerik UI for ASP.NET AJAX through version 2019.3.1023. It is triggered when an attacker who knows the Telerik upload encryption keys — most commonly because the earlier flaws CVE-2017-11317 or CVE-2017-11357 exposed them, though keys can be obtained by other means — sends crafted serialized data to RadAsyncUpload, allowing remote code execution without authentication. Successful exploitation gives an attacker arbitrary code execution on the hosting IIS/ASP.NET web server, reflected in the critical 9.8 CVSS score. Any web application built with Telerik UI for ASP.NET AJAX at or below 2019.3.1023 is affected, unless 2019.3.1023 has the non-default hardening setting enabled (as of 2020.1.114 a default setting prevents the exploit). Exploitation is rampant in the wild: the flaw was added to CISA KEV on 2021-11-03 with known ransomware use, carries a 99.7% EPSS probability of exploitation, has multiple public exploits (Bishop Fox, RAU_crypto, noperator), and has been used by multiple threat groups — including ransomware and government-linked actors — to breach organizations including a U.S. federal agency.

Do: Upgrade to Progress Telerik UI for ASP.NET AJAX 2020.1.114 or later, where a default setting prevents exploitation (or, if staying on 2019.3.1023, enable the non-default hardening setting); per CISA KEV, apply updates per vendor instructions. Because exploitation requires the encryption keys to be known, also patch the older CVE-2017-11317/CVE-2017-11357 key-disclosure flaws or rotate the Telerik upload encryption keys. Check internet-facing IIS/ASP.NET applications for exposed RadAsyncUpload handlers and indicators of compromise, given known ransomware and federal-agency breaches.

An issue found in Progress Telerik JustAssembly through 2018.1.323.2 and JustDecompile through 2018.2.605.0 makes it possible to execute code by decompiling a compiled .NET object (such as DLL or EXE) with an embedded resource file by clicking on the resource.

Telerik.Web.UI in Progress Telerik UI for ASP.NET AJAX before R1 2017 and in R2 releases before R2 2017 SP2 uses weak encryption for the RadAsyncUpload component, allowing unauthenticated remote attackers to forge upload parameters, upload arbitrary files to the web server, and ultimately execute arbitrary code. The flaw is triggered simply by sending crafted requests to the vulnerable upload handler over the network, with no authentication or user interaction required. Successful exploitation gives an attacker arbitrary file upload and remote code execution in the context of the ASP.NET application, which is typically hosted on IIS web servers. Any site or application built with Telerik UI for ASP.NET AJAX is affected, and the weakness is confirmed exploited in the wild: it was added to CISA's Known Exploited Vulnerabilities catalog on 2022-04-11, and related reporting describes multiple hacking groups — including IIS/ASP.NET-focused APT actors — breaching a U.S. federal agency through it.

Do: Upgrade Telerik UI for ASP.NET AJAX to R1 2017 or R2 2017 SP2 (or later) per vendor instructions, and verify the deployed Telerik.Web.UI.dll version in each application's bin folder. Given active in-the-wild exploitation of IIS/ASP.NET applications, review affected web servers for unauthorized uploads and web shells and rotate ASP.NET machine keys used with RadAsyncUpload.

Progress Telerik UI for ASP.NET AJAX (Telerik.Web.UI.dll) before R2 2017 SP1 and Progress Sitefinity before 10.0.6412.0 fail to adequately protect the Telerik.Web.UI.DialogParametersEncryptionKey and the ASP.NET MachineKey (CWE-522, insufficient key/credential protection). A remote, unauthenticated attacker can send crafted requests to the component's encrypted dialog-parameter handler to recover the dialog encryption key and then leak the MachineKey, and a public proof-of-concept exists (Exploit-DB 43873). With the MachineKey in hand, the attacker can forge or decrypt ASP.NET ViewState, upload or download arbitrary files, and inject XSS, which on IIS servers commonly chains to remote code execution via malicious ViewState. Any website or application embedding the vulnerable Telerik UI assembly, including older Sitefinity CMS releases, is affected. The flaw is confirmed exploited in the wild: it is in CISA's Known Exploited Vulnerabilities catalog (added 2021-11-03), carries a 75.1% EPSS score (99th percentile), and its use in ransomware campaigns is unknown.

Do: Upgrade Telerik UI for ASP.NET AJAX to R2 2017 SP1 or later and Sitefinity to 10.0.6412.0 or later per vendor instructions, as required by CISA's KEV listing. After patching, rotate the Telerik.Web.UI.DialogParametersEncryptionKey and the ASP.NET MachineKey, because keys leaked before patching remain usable to forge ViewState. Review IIS logs for requests to Telerik dialog handler endpoints and for unexpected file uploads, downloads, or ViewState-related anomalies.