How to resolve a System.Security.SecurityException with custom code in SSRS


I've created an assembly and referenced it in my Reporting Services report. I've tested the report locally (works), and I then uploaded the report to a report server (doesn't work).

Here is the error that is thrown by the custom code I've written.

Request for the permission of type
mscorlib, Version=,
failed. at
permToken, CodeAccessPermission
demand, StackCrawlMark& stackMark,
Int32 unrestrictedOverride, Int32
create) at
cap, StackCrawlMark& stackMark) at
at [Snipped Method Name] at
ReportExprHostImpl.CustomCodeProxy.[Snipped Method Name] The action that failed was:
Demand The type of the first
permission that failed was:
The Zone of the assembly that failed
was: MyComputer

This project is something I inherited, and I'm not intimately familiar with it. Although I do have the code (now), so I can at least work with it 🙂

I believe the code that is failing is this:

    Dim fio As System.Security.Permissions.FileIOPermission = New System.Security.Permissions.FileIOPermission(Security.Permissions.PermissionState.Unrestricted)

However, this kind of stuff is everywhere too:

Private Declare Function CryptHashData Lib "advapi32.dll" (ByVal hhash As Integer, ByVal pbData As String, ByVal dwDataLen As Integer, ByVal dwFlags As Integer) As Integer

I can see either of these being things that Reporting Services would not accommodate out of the box.

Best Solution


<trust level="Full"/>


try this in web.config

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