diff --git a/src/buffer/katetextline.h b/src/buffer/katetextline.h
--- a/src/buffer/katetextline.h
+++ b/src/buffer/katetextline.h
@@ -412,20 +412,7 @@
      * @param pos position of attribute requested
      * @return value of attribute
      */
-    short attribute(int pos) const
-    {
-        for (int i = 0; i < m_attributesList.size(); ++i) {
-            if (pos >= m_attributesList[i].offset && pos < (m_attributesList[i].offset + m_attributesList[i].length)) {
-                return m_attributesList[i].attributeValue;
-            }
-
-            if (pos < m_attributesList[i].offset) {
-                break;
-            }
-        }
-
-        return 0;
-    }
+    short attribute(int pos) const;
 
     /**
      * set hl continue flag
diff --git a/src/buffer/katetextline.cpp b/src/buffer/katetextline.cpp
--- a/src/buffer/katetextline.cpp
+++ b/src/buffer/katetextline.cpp
@@ -205,4 +205,17 @@
     m_attributesList.append(attribute);
 }
 
+short TextLineData::attribute(int pos) const
+{
+    auto first = std::lower_bound(m_attributesList.cbegin(), m_attributesList.cend(), pos,
+                                  [](const Attribute &x, const int &p) {
+                                      return x.offset + x.length <= p;
+                                  });
+    if (first != m_attributesList.cend() && (*first).offset <= pos && pos < ((*first).offset + (*first).length))
+    {
+        return (*first).attributeValue;
+    }
+    return 0;
+}
+
 }