diff --git a/Directory.Packages.props b/Directory.Packages.props
index a8d460e..820ae21 100644
--- a/Directory.Packages.props
+++ b/Directory.Packages.props
@@ -5,7 +5,7 @@
   </PropertyGroup>
   <ItemGroup>
     <PackageVersion Include="AngleSharp" Version="1.7.2" />
-    <PackageVersion Include="AWSSDK.S3" Version="3.7.511.8" />
+    <PackageVersion Include="AWSSDK.S3" Version="4.0.102.4" />
     <PackageVersion Include="LibGit2Sharp" Version="0.32.0" />
     <PackageVersion Include="Markdig" Version="1.3.2" />
     <PackageVersion Include="Microsoft.AspNetCore.WebSockets" Version="2.3.0" />
diff --git a/src/Netdocs.Plugins/ImportedDocsPlugin.cs b/src/Netdocs.Plugins/ImportedDocsPlugin.cs
index 1bc96e9..6570abe 100644
--- a/src/Netdocs.Plugins/ImportedDocsPlugin.cs
+++ b/src/Netdocs.Plugins/ImportedDocsPlugin.cs
@@ -394,7 +394,10 @@ private async Task<int> ImportS3SourceAsync(SiteContext site, ImportedDocsS3Sour
                 }
 
                 request.ContinuationToken = response.ContinuationToken;
-            } while (response.IsTruncated && !ct.IsCancellationRequested);
+                // AWS SDK v4 made IsTruncated nullable. Unset means the response did not claim
+                // there is more to fetch, so treat anything but an explicit true as the last page
+                // rather than paginating forever.
+            } while (response.IsTruncated == true && !ct.IsCancellationRequested);
 
             _logger.LogInformation("Imported {Count} pages from S3 bucket {Bucket}", count, source.Bucket);
             return count;