An attribute's string literal parameter does not parse correctly for a URL, GUID, or Version.

Since attributes are derived from System..::.Attribute, and attributes are used at compile time, only constant values can be passed to their constructors. Attribute parameters that must represent URLs, GUIDs and Versions cannot be typed as System..::.Uri, System..::.Guid, and System..::.Version, because these types cannot be represented as constants. Instead, they must be represented by strings.

Because the parameter is typed as a string, it is possible that an incorrectly formatted parameter could be passed at compile time.

This rule uses a naming heuristic to find parameters that represent a uniform resource identifier (URI), a Globally Unique Identifier (GUID) or a Version and verifies that the passed value is correct.

Change the parameter string to a correctly formed URL, GUID, or Version.

It is safe to suppress a warning from this rule if the parameter does not represent a URL, GUID, or Version.

The following example shows code for the AssemblyFileVersionAttribute that violates this rule.

using System;
using System.Runtime.InteropServices;

namespace Samples
{
    [AttributeUsage(AttributeTargets.Assembly, Inherited = false)]
    [ComVisible(true)]
    public sealed class AssemblyFileVersionAttribute : Attribute
    {
        public AssemblyFileVersionAttribute(string version) { }

        public string Version { get; set; }
    }

    // Since the parameter is typed as a string, it is possible
    // to pass an invalid version number at compile time. The rule
    // would be violated by the following code: [assembly : AssemblyFileVersion("xxxxx")]
}

The rule is triggered by the following:

• Parameters that contain ‘version’ and cannot be parsed to System.Version.

• Parameters that contain ‘guid’ and cannot be parsed to System.Guid.

• Parameters that contain ‘uri’, 'urn', or ‘url’ and cannot be parsed to System.Uri.

Reference