ASP.NET | Breaking Cybersecurity News | The Hacker News

Federal Civilian Executive Branch (FCEB) agencies are being advised to update their Sitecore instances by September 25, 2025, following the discovery of a security flaw that has come under active exploitation in the wild. The vulnerability , tracked as CVE-2025-53690 , carries a CVSS score of 9.0 out of a maximum of 10.0, indicating critical severity. "Sitecore Experience Manager (XM), Experience Platform (XP), Experience Commerce (XC), and Managed Cloud contain a deserialization of untrusted data vulnerability involving the use of default machine keys," the U.S. Cybersecurity and Infrastructure Security Agency (CISA) said . "This flaw allows attackers to exploit exposed ASP.NET machine keys to achieve remote code execution." Google-owned Mandiant, which discovered the active ViewState deserialization attack, said the activity leveraged a sample machine key that had been exposed in Sitecore deployment guides from 2017 and earlier. The threat intelligence team ...

Microsoft is warning of an insecure practice wherein software developers are incorporating publicly disclosed ASP.NET machine keys from publicly accessible resources, thereby putting their applications in attackers' pathway. The tech giant's threat intelligence team said it observed limited activity in December 2024 that involved an unknown threat actor using a publicly available, static ASP.NET machine key to inject malicious code and deliver the Godzilla post-exploitation framework. It also noted that it has identified over 3,000 publicly disclosed keys that could be used for these types of attacks, which it's calling ViewState code injection attacks . "Whereas many previously known ViewState code injection attacks used compromised or stolen keys that are often sold on dark web forums, these publicly disclosed keys could pose a higher risk because they are available in multiple code repositories and could have been pushed into development code without modificat...