diff --git a/lib/libimhex/include/hex/pattern_language/ast/ast_node_function_call.hpp b/lib/libimhex/include/hex/pattern_language/ast/ast_node_function_call.hpp
index a12019f2d..016247afb 100644
--- a/lib/libimhex/include/hex/pattern_language/ast/ast_node_function_call.hpp
+++ b/lib/libimhex/include/hex/pattern_language/ast/ast_node_function_call.hpp
@@ -76,20 +76,24 @@ namespace hex::pl {
             auto function = functions[this->m_functionName];
             const auto &[min, max] = function.parameterCount;
 
-            if (evaluatedParams.size() >= min && evaluatedParams.size() < max && evaluatedParams.size() + function.defaultParameters.size() >= max) {
+            if (evaluatedParams.size() >= min && evaluatedParams.size() < max) {
                 while (true) {
                     auto remainingParams = max - evaluatedParams.size();
-                    if (remainingParams <= 0) break;
+                    if (remainingParams <= 0)
+                        break;
 
                     auto offset = evaluatedParams.size() - min;
+                    if (offset >= function.defaultParameters.size())
+                        break;
+
                     evaluatedParams.push_back(function.defaultParameters[offset]);
                 }
             }
 
             if (evaluatedParams.size() < min)
-                LogConsole::abortEvaluation(hex::format("too many parameters for function '{0}'. Expected {1} at least", this->m_functionName, min), this);
+                LogConsole::abortEvaluation(hex::format("too few parameters for function '{0}'. Expected {1} at least", this->m_functionName, min), this);
             else if (evaluatedParams.size() > max)
-                LogConsole::abortEvaluation(hex::format("too few parameters for function '{0}'. Expected {1} at most", this->m_functionName, max), this);
+                LogConsole::abortEvaluation(hex::format("too many parameters for function '{0}'. Expected {1} at most", this->m_functionName, max), this);
 
             try {
                 if (function.dangerous && evaluator->getDangerousFunctionPermission() != DangerousFunctionPermission::Allow) {
diff --git a/lib/libimhex/include/hex/pattern_language/ast/ast_node_function_definition.hpp b/lib/libimhex/include/hex/pattern_language/ast/ast_node_function_definition.hpp
index bc544fbc6..8c015d1dd 100644
--- a/lib/libimhex/include/hex/pattern_language/ast/ast_node_function_definition.hpp
+++ b/lib/libimhex/include/hex/pattern_language/ast/ast_node_function_definition.hpp
@@ -48,7 +48,9 @@ namespace hex::pl {
 
             ParameterCount paramCount;
 
-            if (this->m_parameterPack.has_value())
+            if (this->m_parameterPack.has_value() && !this->m_defaultParameters.empty())
+                paramCount = ParameterCount::atLeast(this->m_params.size() - this->m_defaultParameters.size());
+            else if (this->m_parameterPack.has_value())
                 paramCount = ParameterCount::atLeast(this->m_params.size());
             else if (!this->m_defaultParameters.empty())
                 paramCount = ParameterCount::between(this->m_params.size() - this->m_defaultParameters.size(), this->m_params.size());
@@ -84,7 +86,7 @@ namespace hex::pl {
                     ctx->createParameterPack(this->m_parameterPack.value(), parameterPackContent);
                 }
 
-                for (u32 paramIndex = 0; paramIndex < this->m_params.size(); paramIndex++) {
+                for (u32 paramIndex = 0; paramIndex < this->m_params.size() && paramIndex < params.size(); paramIndex++) {
                     const auto &[name, type] = this->m_params[paramIndex];
 
                     ctx->createVariable(name, type.get(), params[paramIndex]);