diff --git a/command/views/json/diagnostic.go b/command/views/json/diagnostic.go
index 12a8d2730..1290e6bb5 100644
--- a/command/views/json/diagnostic.go
+++ b/command/views/json/diagnostic.go
@@ -133,6 +133,12 @@ func NewDiagnostic(diag tfdiags.Diagnostic, sources map[string][]byte) *Diagnost
 		// We'll borrow HCL's range implementation here, because it has some
 		// handy features to help us produce a nice source code snippet.
 		highlightRange := sourceRefs.Subject.ToHCL()
+
+		// Some diagnostic sources fail to set the end of the subject range.
+		if highlightRange.End == (hcl.Pos{}) {
+			highlightRange.End = highlightRange.Start
+		}
+
 		snippetRange := highlightRange
 		if sourceRefs.Context != nil {
 			snippetRange = sourceRefs.Context.ToHCL()
diff --git a/command/views/json/diagnostic_test.go b/command/views/json/diagnostic_test.go
index 8308b18a6..a11d815e2 100644
--- a/command/views/json/diagnostic_test.go
+++ b/command/views/json/diagnostic_test.go
@@ -246,6 +246,44 @@ func TestNewDiagnostic(t *testing.T) {
 				},
 			},
 		},
+		"error with unset highlight end position": {
+			&hcl.Diagnostic{
+				Severity: hcl.DiagError,
+				Summary:  "There is no end",
+				Detail:   "But there is a beginning",
+				Subject: &hcl.Range{
+					Filename: "test.tf",
+					Start:    hcl.Pos{Line: 1, Column: 16, Byte: 15},
+					End:      hcl.Pos{Line: 0, Column: 0, Byte: 0},
+				},
+			},
+			&Diagnostic{
+				Severity: "error",
+				Summary:  "There is no end",
+				Detail:   "But there is a beginning",
+				Range: &DiagnosticRange{
+					Filename: "test.tf",
+					Start: Pos{
+						Line:   1,
+						Column: 16,
+						Byte:   15,
+					},
+					End: Pos{
+						Line:   1,
+						Column: 17,
+						Byte:   16,
+					},
+				},
+				Snippet: &DiagnosticSnippet{
+					Context:              strPtr(`resource "test_resource" "test"`),
+					Code:                 `resource "test_resource" "test" {`,
+					StartLine:            1,
+					HighlightStartOffset: 15,
+					HighlightEndOffset:   16,
+					Values:               []DiagnosticExpressionValue{},
+				},
+			},
+		},
 		"error with source code subject and known expression": {
 			&hcl.Diagnostic{
 				Severity: hcl.DiagError,
@@ -698,6 +736,11 @@ func TestNewDiagnostic(t *testing.T) {
 				"diagnostic",
 				fmt.Sprintf("%s.json", strings.ReplaceAll(name, " ", "-")),
 			)
+
+			// Generate golden reference by uncommenting the next two lines:
+			// gotBytes = append(gotBytes, '\n')
+			// os.WriteFile(filename, gotBytes, 0644)
+
 			wantFile, err := os.Open(filename)
 			if err != nil {
 				t.Fatalf("failed to open golden file: %s", err)
diff --git a/command/views/json/testdata/diagnostic/error-with-unset-highlight-end-position.json b/command/views/json/testdata/diagnostic/error-with-unset-highlight-end-position.json
new file mode 100644
index 000000000..1f7351f09
--- /dev/null
+++ b/command/views/json/testdata/diagnostic/error-with-unset-highlight-end-position.json
@@ -0,0 +1,26 @@
+{
+  "severity": "error",
+  "summary": "There is no end",
+  "detail": "But there is a beginning",
+  "range": {
+    "filename": "test.tf",
+    "start": {
+      "line": 1,
+      "column": 16,
+      "byte": 15
+    },
+    "end": {
+      "line": 1,
+      "column": 17,
+      "byte": 16
+    }
+  },
+  "snippet": {
+    "context": "resource \"test_resource\" \"test\"",
+    "code": "resource \"test_resource\" \"test\" {",
+    "start_line": 1,
+    "highlight_start_offset": 15,
+    "highlight_end_offset": 16,
+    "values": []
+  }
+}