diff --git a/apport/report.py b/apport/report.py
index c828c8b63..28cfb79c4 100644
--- a/apport/report.py
+++ b/apport/report.py
@@ -1620,8 +1620,9 @@ def standard_title(self) -> str | None:
         # package problem
         if self.get("ProblemType") == "Package" and "Package" in self:
             title = f"package {self['Package']} failed to install/upgrade"
-            if self.get("ErrorMessage"):
-                title += ": " + self["ErrorMessage"].splitlines()[-1]
+            error_message = self.get("ErrorMessage")
+            if error_message and isinstance(error_message, str):
+                title += ": " + error_message.splitlines()[-1]
 
             return title
 
diff --git a/data/general-hooks/generic.py b/data/general-hooks/generic.py
index 879fd3f6f..ddf567869 100644
--- a/data/general-hooks/generic.py
+++ b/data/general-hooks/generic.py
@@ -104,8 +104,10 @@ def add_info(report: ProblemReport, ui: apport.hook_ui.HookUI) -> None:
             " which the crashed program expected to use."
         )
     # filter out package install failures due to a segfault
+    error_message = report.get("ErrorMessage")
     if (
-        "Segmentation fault" in report.get("ErrorMessage", "")
+        isinstance(error_message, str)
+        and "Segmentation fault" in error_message
         and report["ProblemType"] == "Package"
     ):
         report["UnreportableReason"] = (