Fixed #261 (CBOR, BigInteger)

Author: cowtowncoder

cbor/src/main/java/com/fasterxml/jackson/dataformat/cbor/CBORParser.java

@@ -851,11 +851,16 @@ protected JsonToken _handleTaggedBinary(int tag) throws IOException
         // First: get the data
         _finishToken();
 
-        BigInteger nr = new BigInteger(_binaryValue);
-        if (neg) {
-            nr = nr.negate();
+        // [dataformats-binar#261]: handle this special case
+        if (_binaryValue.length == 0) {
+            _numberBigInt = BigInteger.ZERO;
+        } else {
+            BigInteger nr = new BigInteger(_binaryValue);
+            if (neg) {
+                nr = nr.negate();
+            }
+            _numberBigInt = nr;
         }
-        _numberBigInt = nr;
         _numTypesValid = NR_BIGINT;
         _tagValue = -1;
         return (_currToken = JsonToken.VALUE_NUMBER_INT);

cbor/src/test/java/com/fasterxml/jackson/dataformat/cbor/fuzz/Fuzz32173ShortTextTest.java renamed to cbor/src/test/java/com/fasterxml/jackson/dataformat/cbor/fuzz/Fuzz32173LongTextTest.java

@@ -6,7 +6,7 @@
 
 import com.fasterxml.jackson.dataformat.cbor.CBORTestBase;
 
-public class Fuzz32173ShortTextTest extends CBORTestBase
+public class Fuzz32173LongTextTest extends CBORTestBase
 {
     private final ObjectMapper MAPPER = cborMapper();
 
@@ -23,5 +23,4 @@ public void testInvalidShortText() throws Exception
             verifyException(e, "Unexpected end-of-input in VALUE_STRING");
         }
     }
-
 }

cbor/src/test/java/com/fasterxml/jackson/dataformat/cbor/fuzz/Fuzz32250BigIntegerTest.java

@@ -0,0 +1,24 @@
+package com.fasterxml.jackson.dataformat.cbor.fuzz;
+
+import java.math.BigInteger;
+
+import com.fasterxml.jackson.databind.JsonNode;
+import com.fasterxml.jackson.databind.ObjectMapper;
+import com.fasterxml.jackson.dataformat.cbor.CBORTestBase;
+
+public class Fuzz32250BigIntegerTest extends CBORTestBase
+{
+    private final ObjectMapper MAPPER = cborMapper();
+
+    public void testInvalidShortText() throws Exception
+    {
+        final byte[] input = new byte[] {
+                (byte) 0xC3,
+                0x5F, (byte) 0xFF
+        };
+        JsonNode root = MAPPER.readTree(input);
+        assertTrue(root.isNumber());
+        assertTrue(root.isBigInteger());
+        assertEquals(BigInteger.ZERO, root.bigIntegerValue());
+    }
+}

release-notes/CREDITS-2.x

@@ -172,6 +172,8 @@ Fabian Meumertzheim (fmeum@github)
 * Reported #259: (cbor) Failed to handle case of alleged String with length of
   Integer.MAX_VALUE
  (2.12.3)
+* Reported #261 (cbor) CBORParser need to validate zero-length byte[] for BigInteger
+ (2.12.3)
 
 (jhhladky@github)
 

release-notes/VERSION-2.x

@@ -18,6 +18,8 @@ Modules:
  (reported by Fabian M)
 #259: (cbor) Failed to handle case of alleged String with length of Integer.MAX_VALUE
  (reported by Fabian M)
+#261 (cbor) CBORParser need to validate zero-length byte[] for BigInteger 
+ (reported by Fabian M)
 
 2.12.2 (03-Mar-2021)