diff --git a/Adjust/ADJActivityHandler.m b/Adjust/ADJActivityHandler.m
index 04139c291..810d05ec1 100644
--- a/Adjust/ADJActivityHandler.m
+++ b/Adjust/ADJActivityHandler.m
@@ -1337,6 +1337,7 @@ - (BOOL)readDeeplinkQueryStringI:(ADJActivityHandler *)selfI
     if (value.length == 0) return NO;
 
     NSString* valueDecoded = [value adjUrlDecode];
+    if (!valueDecoded) return NO;
 
     NSString* keyWOutPrefix = [keyDecoded substringFromIndex:kAdjustPrefix.length];
     if (keyWOutPrefix.length == 0) return NO;