diff --git a/apps/openmw_test_suite/nifloader/testbulletnifloader.cpp b/apps/openmw_test_suite/nifloader/testbulletnifloader.cpp
index 3044bf2704..36f2512462 100644
--- a/apps/openmw_test_suite/nifloader/testbulletnifloader.cpp
+++ b/apps/openmw_test_suite/nifloader/testbulletnifloader.cpp
@@ -266,7 +266,7 @@ namespace
         MOCK_CONST_METHOD0(numRecords, std::size_t ());
         MOCK_CONST_METHOD1(getRoot, Nif::Record* (std::size_t));
         MOCK_CONST_METHOD0(numRoots, std::size_t ());
-        MOCK_CONST_METHOD1(getString, std::string (std::size_t));
+        MOCK_CONST_METHOD1(getString, std::string (uint32_t));
         MOCK_METHOD1(setUseSkinning, void (bool));
         MOCK_CONST_METHOD0(getUseSkinning, bool ());
         MOCK_CONST_METHOD0(getFilename, std::string ());
diff --git a/components/bsa/compressedbsafile.cpp b/components/bsa/compressedbsafile.cpp
index ba96ee8de9..d0bebe3c1f 100644
--- a/components/bsa/compressedbsafile.cpp
+++ b/components/bsa/compressedbsafile.cpp
@@ -422,7 +422,8 @@ void CompressedBSAFile::convertCompressedSizesToUncompressed()
 std::uint64_t CompressedBSAFile::generateHash(std::string stem, std::string extension) const
 {
     size_t len = stem.length();
-    if (len == 0) return 0;
+    if (len == 0)
+        return 0;
     std::uint64_t hash = 0;
     unsigned int hash2 = 0;
     Misc::StringUtils::lowerCaseInPlace(stem);
@@ -434,12 +435,19 @@ std::uint64_t CompressedBSAFile::generateHash(std::string stem, std::string exte
         for (const char &c : extension)
             hash = hash * 0x1003f + c;
     }
-    for (size_t i = 1; i < len-2 && len > 3; i++)
-        hash2 = hash2 * 0x1003f + stem[i];
+    if (len >= 4)
+    {
+        for (size_t i = 1; i < len-2; i++)
+            hash2 = hash2 * 0x1003f + stem[i];
+    }
     hash = (hash + hash2) << 32;
     hash2 = (stem[0] << 24) | (len << 16);
-    if (len >= 3) hash2 |= stem[len-2] << 8;
-    if (len >= 2) hash2 |= stem[len-1];
+    if (len >= 2)
+    {
+        if (len >= 3)
+            hash2 |= stem[len-2] << 8;
+        hash2 |= stem[len-1];
+    }
     if (!extension.empty())
     {
         if (extension == ".kf")       hash2 |= 0x80;
diff --git a/components/nif/niffile.hpp b/components/nif/niffile.hpp
index e63a7ce733..4d5620a376 100644
--- a/components/nif/niffile.hpp
+++ b/components/nif/niffile.hpp
@@ -26,7 +26,7 @@ struct File
 
     virtual size_t numRoots() const = 0;
 
-    virtual std::string getString(size_t index) const = 0;
+    virtual std::string getString(uint32_t index) const = 0;
 
     virtual void setUseSkinning(bool skinning) = 0;
 
@@ -129,8 +129,10 @@ public:
     size_t numRoots() const override { return roots.size(); }
 
     /// Get a given string from the file's string table
-    std::string getString(size_t index) const override
+    std::string getString(uint32_t index) const override
     {
+        if (index == std::numeric_limits<uint32_t>::max())
+            return std::string();
         return strings.at(index);
     }