diff --git a/utbot-core/src/main/kotlin/org/utbot/common/FileUtil.kt b/utbot-core/src/main/kotlin/org/utbot/common/FileUtil.kt
index 45e1a0248c..86989019b9 100644
--- a/utbot-core/src/main/kotlin/org/utbot/common/FileUtil.kt
+++ b/utbot-core/src/main/kotlin/org/utbot/common/FileUtil.kt
@@ -105,7 +105,7 @@ object FileUtil {
         return tempDir
     }
 
-    private fun URI.extractJarName(): URI = URI(this.schemeSpecificPart.substringBefore("!"))
+    private fun URI.extractJarName(): URI = URI(this.schemeSpecificPart.substringBefore("!").replace(" ", "%20"))
 
     private fun extractClassFromArchive(archiveFile: Path, clazz: KClass<*>, destPath: Path) {
         val classFilePath = clazz.toClassFilePath()