Index: src/OFString+JSONValue.m
==================================================================
--- src/OFString+JSONValue.m
+++ src/OFString+JSONValue.m
@@ -256,10 +256,14 @@
 			}
 
 			(*pointer)++;
 
 			return ret;
+		/* Newlines in strings are disallowed */
+		} else if (**pointer == '\n' || **pointer == '\r') {
+			free(buffer);
+			return nil;
 		} else {
 			buffer[i++] = **pointer;
 			(*pointer)++;
 		}
 	}