diff --git a/src/specify_cli/integrations/catalog.py b/src/specify_cli/integrations/catalog.py
index aba5877d8f..c9797934b5 100644
--- a/src/specify_cli/integrations/catalog.py
+++ b/src/specify_cli/integrations/catalog.py
@@ -429,7 +429,8 @@ def add_catalog(self, url: str, name: Optional[str] = None) -> None:
                     )
                 try:
                     normalized_priority = int(raw_priority)
-                except (TypeError, ValueError):
+                except (TypeError, ValueError, OverflowError):
+                    # OverflowError: int(float("inf")) — a ``priority: .inf``.
                     raise IntegrationValidationError(
                         f"Invalid catalog entry at index {idx} in {config_path}: "
                         f"'priority' must be an integer, got "
@@ -537,7 +538,8 @@ def _is_removable_catalog_entry(item: Any) -> bool:
             else:
                 try:
                     priority = int(raw_priority)
-                except (TypeError, ValueError):
+                except (TypeError, ValueError, OverflowError):
+                    # OverflowError: int(float("inf")) — a ``priority: .inf``.
                     priority = yaml_idx + 1
             priority_pairs.append((priority, yaml_idx))
         if not priority_pairs:
diff --git a/tests/integrations/test_integration_catalog.py b/tests/integrations/test_integration_catalog.py
index a0323b3ea6..3ab9c3612e 100644
--- a/tests/integrations/test_integration_catalog.py
+++ b/tests/integrations/test_integration_catalog.py
@@ -922,6 +922,57 @@ def test_add_catalog_rejects_non_mapping_entry_with_config_path(
         assert str(cfg_path) in message
         assert "expected a mapping" in message
 
+    def test_add_catalog_rejects_inf_priority_in_existing_entry(
+        self, tmp_path, monkeypatch
+    ):
+        # ``priority: .inf`` loads as float('inf'); int() on it raises
+        # OverflowError, which used to escape the IntegrationValidationError
+        # contract as a raw traceback (github/spec-kit#3526 fixed the sibling
+        # workflow/step loaders the same way).
+        self._isolate(tmp_path, monkeypatch)
+        cfg_path = tmp_path / ".specify" / "integration-catalogs.yml"
+        cfg_path.write_text(
+            yaml.dump(
+                {
+                    "catalogs": [
+                        {
+                            "url": "https://a.example.com/catalog.json",
+                            "priority": float("inf"),
+                        }
+                    ]
+                }
+            ),
+            encoding="utf-8",
+        )
+        cat = IntegrationCatalog(tmp_path)
+        with pytest.raises(
+            IntegrationValidationError, match="must be an integer"
+        ):
+            cat.add_catalog("https://new.example.com/catalog.json")
+
+    def test_remove_catalog_tolerates_inf_priority(self, tmp_path, monkeypatch):
+        # Building the remove display order must not crash on a ``priority:
+        # .inf`` entry; it falls back to positional order like the other
+        # non-integer priorities do.
+        self._isolate(tmp_path, monkeypatch)
+        cfg_path = tmp_path / ".specify" / "integration-catalogs.yml"
+        cfg_path.write_text(
+            yaml.dump(
+                {
+                    "catalogs": [
+                        {
+                            "url": "https://a.example.com/catalog.json",
+                            "priority": float("inf"),
+                        },
+                        {"url": "https://b.example.com/catalog.json", "priority": 2},
+                    ]
+                }
+            ),
+            encoding="utf-8",
+        )
+        cat = IntegrationCatalog(tmp_path)
+        cat.remove_catalog(0)  # must not raise OverflowError
+
     def test_add_catalog_skips_blank_url_entries(self, tmp_path, monkeypatch):
         self._isolate(tmp_path, monkeypatch)
         cfg_path = tmp_path / ".specify" / "integration-catalogs.yml"