Oliver Dewdney

**Name of the Vulnerable Software and Affected Versions** Microsoft .NET Framework versions 1.1 SP1 through 4.0 **Description** The issue arises from the Forms Authentication feature in the ASP.NET subsystem when sliding expiry is enabled, leading to improper handling of cached content. This allows remote attackers to obtain access to arbitrary user accounts via a crafted URL. An elevation of privilege vulnerability exists, enabling an attacker to take any action, including executing arbitrary commands, in the context of the target user. Exploitation can occur through email attacks, where an attacker sends a specially crafted link to the user, convincing them to click it. **Recommendations** For Microsoft .NET Framework versions 1.1 SP1 through 4.0, consider disabling the Forms Authentication feature with sliding expiry as a temporary workaround until a patch is available. Restrict access to cached content to minimize the risk of exploitation. Avoid using crafted URLs that could lead to arbitrary user account access until the issue is resolved. At the moment, there is no information about a newer version that contains a fix for this vulnerability.