diff --git a/Ghidra/Features/Base/src/main/java/ghidra/app/util/bin/format/omf/Omf2or4.java b/Ghidra/Features/Base/src/main/java/ghidra/app/util/bin/format/omf/Omf2or4.java
index f21d076560..a12709c95a 100644
--- a/Ghidra/Features/Base/src/main/java/ghidra/app/util/bin/format/omf/Omf2or4.java
+++ b/Ghidra/Features/Base/src/main/java/ghidra/app/util/bin/format/omf/Omf2or4.java
@@ -4,9 +4,9 @@
  * Licensed under the Apache License, Version 2.0 (the "License");
  * you may not use this file except in compliance with the License.
  * You may obtain a copy of the License at
- * 
+ *
  *      http://www.apache.org/licenses/LICENSE-2.0
- * 
+ *
  * Unless required by applicable law or agreed to in writing, software
  * distributed under the License is distributed on an "AS IS" BASIS,
  * WITHOUT WARRANTIES OR CONDITIONS OF ANY KIND, either express or implied.
@@ -23,36 +23,11 @@ import ghidra.util.exception.DuplicateNameException;
 
 /**
  * An OMF value that is either 2 or 4 bytes
+ *
+ * @param length 2 or 4
+ * @param value The 2 or 4 byte value
  */
-public class Omf2or4 implements StructConverter {
-
-	private int length;
-	private long value;
-
-	/**
-	 * Creates a new {@link Omf2or4}
-	 * 
-	 * @param length 2 or 4
-	 * @param value The 2 or 4 byte value
-	 */
-	public Omf2or4(int length, long value) {
-		this.length = length;
-		this.value = value;
-	}
-
-	/**
-	 * {@return the length of the value (2 or 4)}
-	 */
-	public int length() {
-		return length;
-	}
-
-	/**
-	 * {@return the value}
-	 */
-	public long value() {
-		return value;
-	}
+public record Omf2or4(int length, long value) implements StructConverter {
 
 	@Override
 	public DataType toDataType() throws DuplicateNameException, IOException {
diff --git a/Ghidra/Features/Base/src/main/java/ghidra/app/util/bin/format/omf/OmfUtils.java b/Ghidra/Features/Base/src/main/java/ghidra/app/util/bin/format/omf/OmfUtils.java
index a93cff8ed9..6b227b9c68 100644
--- a/Ghidra/Features/Base/src/main/java/ghidra/app/util/bin/format/omf/OmfUtils.java
+++ b/Ghidra/Features/Base/src/main/java/ghidra/app/util/bin/format/omf/OmfUtils.java
@@ -35,7 +35,7 @@ public class OmfUtils {
 	public static final String CATEGORY_PATH = "/OMF";
 
 	public static Omf2or4 readInt2Or4(BinaryReader reader, boolean isBig) throws IOException {
-		return isBig ? new Omf2or4(4, reader.readNextInt())
+		return isBig ? new Omf2or4(4, reader.readNextUnsignedInt())
 				: new Omf2or4(2, reader.readNextUnsignedShort());
 	}
 
diff --git a/Ghidra/Features/Base/src/main/java/ghidra/app/util/bin/format/omf/omf/OmfIteratedData.java b/Ghidra/Features/Base/src/main/java/ghidra/app/util/bin/format/omf/omf/OmfIteratedData.java
index f6a221ea9c..faf9f03c49 100644
--- a/Ghidra/Features/Base/src/main/java/ghidra/app/util/bin/format/omf/omf/OmfIteratedData.java
+++ b/Ghidra/Features/Base/src/main/java/ghidra/app/util/bin/format/omf/omf/OmfIteratedData.java
@@ -4,9 +4,9 @@
  * Licensed under the Apache License, Version 2.0 (the "License");
  * you may not use this file except in compliance with the License.
  * You may obtain a copy of the License at
- * 
+ *
  *      http://www.apache.org/licenses/LICENSE-2.0
- * 
+ *
  * Unless required by applicable law or agreed to in writing, software
  * distributed under the License is distributed on an "AS IS" BASIS,
  * WITHOUT WARRANTIES OR CONDITIONS OF ANY KIND, either express or implied.
@@ -19,7 +19,8 @@ import java.io.IOException;
 import java.util.ArrayList;
 
 import ghidra.app.util.bin.BinaryReader;
-import ghidra.app.util.bin.format.omf.*;
+import ghidra.app.util.bin.format.omf.OmfException;
+import ghidra.app.util.bin.format.omf.OmfUtils;
 import ghidra.program.model.data.DataType;
 import ghidra.util.exception.DuplicateNameException;
 
@@ -83,14 +84,17 @@ public class OmfIteratedData extends OmfData {
 	 * Contain the definition of one part of a datablock with possible recursion
 	 */
 	public static class DataBlock {
-		private Omf2or4 repeatCount;
+		private int repeatCount;
 		private int blockCount;
 		private byte[] simpleBlock = null;
 		private DataBlock[] nestedBlock = null;
 
 		public static DataBlock read(BinaryReader reader, boolean hasBigFields) throws IOException {
 			DataBlock subblock = new DataBlock();
-			subblock.repeatCount = OmfUtils.readInt2Or4(reader, hasBigFields);
+			subblock.repeatCount = (int) OmfUtils.readInt2Or4(reader, hasBigFields).value();
+			if (subblock.repeatCount < 0) {
+				throw new IOException("Iterated block has negative repeat count");
+			}
 			subblock.blockCount = reader.readNextUnsignedShort();
 			if (subblock.blockCount == 0) {
 				int size = reader.readNextByte() & 0xff;
@@ -115,7 +119,7 @@ public class OmfIteratedData extends OmfData {
 		 * @return The position after the block
 		 */
 		public int fillBuffer(byte[] buffer, int pos) {
-			for (int i = 0; i < (int) repeatCount.value(); ++i) {
+			for (int i = 0; i < repeatCount; ++i) {
 				if (simpleBlock != null) {
 					for (byte element : simpleBlock) {
 						buffer[pos] = element;
@@ -144,7 +148,7 @@ public class OmfIteratedData extends OmfData {
 					length += block.getLength();
 				}
 			}
-			return length * (int) repeatCount.value();
+			return length * repeatCount;
 		}
 
 		/**
diff --git a/Ghidra/Features/Base/src/main/java/ghidra/app/util/bin/format/pef/ContainerHeader.java b/Ghidra/Features/Base/src/main/java/ghidra/app/util/bin/format/pef/ContainerHeader.java
index 511fab80d8..d13813089d 100644
--- a/Ghidra/Features/Base/src/main/java/ghidra/app/util/bin/format/pef/ContainerHeader.java
+++ b/Ghidra/Features/Base/src/main/java/ghidra/app/util/bin/format/pef/ContainerHeader.java
@@ -15,14 +15,14 @@
  */
 package ghidra.app.util.bin.format.pef;
 
-import ghidra.app.util.bin.*;
-import ghidra.program.model.data.*;
-import ghidra.util.exception.DuplicateNameException;
-
 import java.io.IOException;
 import java.util.ArrayList;
 import java.util.List;
 
+import ghidra.app.util.bin.*;
+import ghidra.program.model.data.*;
+import ghidra.util.exception.DuplicateNameException;
+
 /**
  * See Apple's -- PEFBinaryFormat.h
  * <pre>
@@ -103,6 +103,10 @@ public class ContainerHeader implements StructConverter {
 			}
 			_sections.add(section);
 		}
+
+		if (_loader == null) {
+			throw new PefException("Loader section not found!");
+		}
 	}
 
 	/**
diff --git a/Ghidra/Features/Base/src/main/java/ghidra/app/util/bin/format/pef/SectionHeader.java b/Ghidra/Features/Base/src/main/java/ghidra/app/util/bin/format/pef/SectionHeader.java
index 858d4e287d..d1ed148306 100644
--- a/Ghidra/Features/Base/src/main/java/ghidra/app/util/bin/format/pef/SectionHeader.java
+++ b/Ghidra/Features/Base/src/main/java/ghidra/app/util/bin/format/pef/SectionHeader.java
@@ -4,9 +4,9 @@
  * Licensed under the Apache License, Version 2.0 (the "License");
  * you may not use this file except in compliance with the License.
  * You may obtain a copy of the License at
- * 
+ *
  *      http://www.apache.org/licenses/LICENSE-2.0
- * 
+ *
  * Unless required by applicable law or agreed to in writing, software
  * distributed under the License is distributed on an "AS IS" BASIS,
  * WITHOUT WARRANTIES OR CONDITIONS OF ANY KIND, either express or implied.
@@ -113,8 +113,9 @@ public class SectionHeader implements StructConverter {
 	 * @param monitor the task monitor
 	 * @return the unpacked data
 	 * @throws IOException if an i/o error occurs or the section is not packed.
+	 * @throws IllegalStateException an an unexpected state occurs
 	 */
-	public byte[] getUnpackedData(TaskMonitor monitor) throws IOException {
+	public byte[] getUnpackedData(TaskMonitor monitor) throws IOException, IllegalStateException {
 		if (getSectionKind() != SectionKind.PackedData) {
 			throw new IOException("Attempt to unpack a section that is not packed.");
 		}
@@ -127,7 +128,7 @@ public class SectionHeader implements StructConverter {
 				}
 				int value = input.read();
 				if (value == -1) {
-					throw new IllegalStateException();
+					throw new IllegalStateException("Unexpectedly reached end-of-file");
 				}
 				int count = value & 0x1f;//count is the lower 5 bits...
 				if (count == 0) {
@@ -218,11 +219,14 @@ public class SectionHeader implements StructConverter {
 		}
 	}
 
-	private int unpackNextValue(InputStream input) throws IOException {
+	private int unpackNextValue(InputStream input) throws IOException, IllegalStateException {
 		int unpacked = 0;
 		while (true) {
 			unpacked <<= 7;
 			int value = input.read();
+			if (value == -1) {
+				throw new IllegalStateException("Unexpectedly reached end-of-file");
+			}
 			unpacked += (value & 0x7f);
 			if ((value & 0x80) == 0x00) {
 				break;
diff --git a/Ghidra/Features/Base/src/main/java/ghidra/app/util/opinion/PefLoader.java b/Ghidra/Features/Base/src/main/java/ghidra/app/util/opinion/PefLoader.java
index 3d274bc7e2..7b3dde1bd7 100644
--- a/Ghidra/Features/Base/src/main/java/ghidra/app/util/opinion/PefLoader.java
+++ b/Ghidra/Features/Base/src/main/java/ghidra/app/util/opinion/PefLoader.java
@@ -35,6 +35,14 @@ import ghidra.program.model.symbol.*;
 import ghidra.util.exception.CancelledException;
 import ghidra.util.task.TaskMonitor;
 
+/**
+ * A {@link Loader} for Preferred Executable Format (PEF) files.
+ * <p>
+ * PEF was developed by Apple for use in its classic Mac OS operating system. BeOS on PowerPC 
+ * systems also uses PEF.
+ * 
+ * @see <a href="https://web.archive.org/web/20011017102300/http://developer.apple.com/techpubs/mac/runtimehtml/RTArch-89.html">PEF Structure</a>
+ */
 public class PefLoader extends AbstractProgramWrapperLoader {
 
 	public final static String PEF_NAME = "Preferred Executable Format (PEF)";