diff --git a/avro/src/main/java/com/fasterxml/jackson/dataformat/avro/deser/JacksonAvroParserImpl.java b/avro/src/main/java/com/fasterxml/jackson/dataformat/avro/deser/JacksonAvroParserImpl.java
index 15c51549b..688704814 100644
--- a/avro/src/main/java/com/fasterxml/jackson/dataformat/avro/deser/JacksonAvroParserImpl.java
+++ b/avro/src/main/java/com/fasterxml/jackson/dataformat/avro/deser/JacksonAvroParserImpl.java
@@ -614,9 +614,8 @@ private final String _finishShortText(int len) throws IOException
         _inputPtr += len;
         final byte[] inputBuf = _inputBuffer;
 
-        // Let's actually do a tight loop for ASCII first:
         final int end = inPtr + len;
-
+        // Let's actually do a tight loop for ASCII first:
         int i;
         while ((i = inputBuf[inPtr]) >= 0) {
             outBuf[outPtr++] = (char) i;
@@ -628,9 +627,18 @@ private final String _finishShortText(int len) throws IOException
         final int[] codes = sUtf8UnitLengths;
         do {
             i = inputBuf[inPtr++] & 0xFF;
-            switch (codes[i]) {
-            case 0:
-                break;
+            final int code = codes[i];
+            if (code == 0) { // still optimized for ASCII
+                outBuf[outPtr++] = (char) i;
+                continue;
+            }
+            if ((inPtr + code) > end) {
+                if (code < 4) {
+                    throw _constructError(String.format(
+                            "Malformed %d-byte UTF-8 character at the end of Unicode text block", code));
+                }
+            }
+            switch (code) {
             case 1:
                 i = ((i & 0x1F) << 6) | (inputBuf[inPtr++] & 0x3F);
                 break;
@@ -650,7 +658,7 @@ private final String _finishShortText(int len) throws IOException
                 i = 0xDC00 | (i & 0x3FF);
                 break;
             default: // invalid
-                _reportError("Invalid byte "+Integer.toHexString(i)+" in Unicode text block");
+                _reportError(String.format("Invalid byte 0x2X in Unicode text block", i));
             }
             outBuf[outPtr++] = (char) i;
         } while (inPtr < end);
diff --git a/avro/src/test/java/com/fasterxml/jackson/dataformat/avro/fuzz/AvroFuzz449_65618_IOOBETest.java b/avro/src/test/java/com/fasterxml/jackson/dataformat/avro/fuzz/AvroFuzz449_65618_IOOBETest.java
new file mode 100644
index 000000000..fbcc2df6c
--- /dev/null
+++ b/avro/src/test/java/com/fasterxml/jackson/dataformat/avro/fuzz/AvroFuzz449_65618_IOOBETest.java
@@ -0,0 +1,45 @@
+package com.fasterxml.jackson.dataformat.avro.fuzz;
+
+import org.junit.Test;
+
+import com.fasterxml.jackson.annotation.JsonPropertyOrder;
+import com.fasterxml.jackson.core.JsonToken;
+import com.fasterxml.jackson.core.exc.StreamReadException;
+import com.fasterxml.jackson.dataformat.avro.AvroFactory;
+import com.fasterxml.jackson.dataformat.avro.AvroMapper;
+import com.fasterxml.jackson.dataformat.avro.AvroParser;
+import com.fasterxml.jackson.dataformat.avro.AvroSchema;
+import com.fasterxml.jackson.dataformat.avro.AvroTestBase;
+
+// [dataformats-binary#449]
+public class AvroFuzz449_65618_IOOBETest extends AvroTestBase
+{
+    @JsonPropertyOrder({ "name", "value" })
+    static class RootType {
+        public String name;
+        public int value;
+    }
+
+    @Test
+    public void testFuzz65618IOOBE() throws Exception {
+        final AvroFactory factory = AvroFactory.builderWithApacheDecoder().build();
+        final AvroMapper mapper = new AvroMapper(factory);
+
+        final byte[] doc = {
+            (byte) 2, (byte) 22, (byte) 36, (byte) 2, (byte) 0,
+            (byte) 0, (byte) 8, (byte) 3, (byte) 3, (byte) 3,
+            (byte) 122, (byte) 3, (byte) -24
+        };
+
+        final AvroSchema schema = mapper.schemaFor(RootType.class);
+        try (AvroParser p = factory.createParser(doc)) {
+            p.setSchema(schema);
+            assertToken(JsonToken.START_OBJECT, p.nextToken());
+            assertToken(JsonToken.FIELD_NAME, p.nextToken());
+            p.nextToken();
+            fail("Should not pass (invalid content)");
+        } catch (StreamReadException e) {
+            verifyException(e, "Malformed 2-byte UTF-8 character at the end of");
+        }
+    }
+}
diff --git a/release-notes/CREDITS-2.x b/release-notes/CREDITS-2.x
index 8710ceb67..d354d3c0b 100644
--- a/release-notes/CREDITS-2.x
+++ b/release-notes/CREDITS-2.x
@@ -295,5 +295,9 @@ Arthur Chan (@arthurscchan)
  * Contributed #432 (ion) More methods from `IonReader` could throw an unexpected
    `AssertionError`
   (2.17.0)
- * Contributed #434 (ion) Unexpected `NullPointerException` thrown from `IonParser::getNumberType()`
+ * Contributed #434: (ion) Unexpected `NullPointerException` thrown from
+  `IonParser::getNumberType()`
+  (2.17.0)
+ * Contributed #449: (avro) `IndexOutOfBoundsException` in `JacksonAvroParserImpl`
+   for invalid input
   (2.17.0)
diff --git a/release-notes/VERSION-2.x b/release-notes/VERSION-2.x
index 0123f86c4..e4856ef0a 100644
--- a/release-notes/VERSION-2.x
+++ b/release-notes/VERSION-2.x
@@ -31,6 +31,8 @@ Active maintainers:
 #434 (ion) Unexpected `NullPointerException` thrown from `IonParser::getNumberType()`
  (fix contributed by Arthur C)
 #437 (ion) `IonReader.next()` throws NPEs for some invalid content
+#449 (avro) `IndexOutOfBoundsException` in `JacksonAvroParserImpl` for invalid input
+ (fix contributed by Arthur C)
 - (ion) Update `com.amazon.ion:ion-java` to 1.11.0 (from 1.10.5)
 
 2.16.1 (24-Dec-2023)