From https://github.com/NationalSecurityAgency/ghidra/pull/490

Index: GPL/CabExtract/build.gradle
--- GPL/CabExtract/build.gradle.orig
+++ GPL/CabExtract/build.gradle
@@ -58,7 +58,7 @@ task configureCabExtract (type: Exec) {
  * The cabextract tool requires that its 'configure' script is called before make.
  *********************************************************************************/
 def currentPlatform = getCurrentPlatformName()
-if (['linux64', 'osx64'].contains(currentPlatform)) {
+if (['linux64', 'osx64', 'openbsd64'].contains(currentPlatform)) {
 		
 	def makeName = "${currentPlatform}CabExtractMake" // native Make task found automatically
 
@@ -75,4 +75,4 @@ if (['linux64', 'osx64'].contains(currentPlatform)) {
 			delete file("build/unpack/${cabextract}")
 		}
 	}
-}
\ No newline at end of file
+}