CVE-2019-18935

Progress Telerik UI for ASP.NET AJAX through 2019.3.1023 contains a .NET deserialization vulnerability in the RadAsyncUpload function. This is exploitable when the encryption keys are known due to the presence of CVE-2017-11317 or CVE-2017-11357, or other means. Exploitation can result in remote code execution. (As of 2020.1.114, a default setting prevents the exploit. In 2019.3.1023, but not earlier versions, a non-default setting can prevent exploitation.)

Weakness

The product deserializes untrusted data without sufficiently ensuring that the resulting data will be valid.

Affected Software

Potential Mitigations

• Make fields transient to protect them from deserialization.
• An attempt to serialize and then deserialize a class containing transient fields will result in NULLs where the transient data should be. This is an excellent way to prevent time, environment-based, or sensitive variables from being carried over and used improperly.

Related Attack Patterns

• https://cwe.mitre.org/data/definitions/586.html

References

• http://packetstormsecurity.com/files/155720/Telerik-UI-Remote-Code-Execution.html
• http://packetstormsecurity.com/files/159653/Telerik-UI-ASP.NET-AJAX-RadAsyncUpload-Deserialization.html
• https://codewhitesec.blogspot.com/2019/02/telerik-revisited.html
• https://github.com/bao7uo/RAU_crypto
• https://github.com/noperator/CVE-2019-18935
• https://know.bishopfox.com/research/cve-2019-18935-remote-code-execution-in-telerik-ui
• https://www.bleepingcomputer.com/news/security/us-federal-agency-hacked-using-old-telerik-bug-to-steal-data/
• https://www.telerik.com/support/kb/aspnet-ajax/details/allows-javascriptserializer-deserialization
• https://www.telerik.com/support/whats-new/aspnet-ajax/release-history/ui-for-asp-net-ajax-r1-2020-%28version-2020-1-114%29
• https://www.telerik.com/support/whats-new/release-history
• http://packetstormsecurity.com/files/155720/Telerik-UI-Remote-Code-Execution.html
• http://packetstormsecurity.com/files/159653/Telerik-UI-ASP.NET-AJAX-RadAsyncUpload-Deserialization.html
• https://codewhitesec.blogspot.com/2019/02/telerik-revisited.html
• https://github.com/bao7uo/RAU_crypto
• https://github.com/noperator/CVE-2019-18935
• https://know.bishopfox.com/research/cve-2019-18935-remote-code-execution-in-telerik-ui
• https://www.bleepingcomputer.com/news/security/us-federal-agency-hacked-using-old-telerik-bug-to-steal-data/
• https://www.telerik.com/support/kb/aspnet-ajax/details/allows-javascriptserializer-deserialization
• https://www.telerik.com/support/whats-new/aspnet-ajax/release-history/ui-for-asp-net-ajax-r1-2020-%28version-2020-1-114%29
• https://www.telerik.com/support/whats-new/release-history