diff --git a/net-misc/xmrig-mo/files/xmrig-mo-6.21.2-fix-length-error.patch b/net-misc/xmrig-mo/files/xmrig-mo-6.21.2-fix-length-error.patch
new file mode 100644
index 0000000000..55a9bde7a6
--- /dev/null
+++ b/net-misc/xmrig-mo/files/xmrig-mo-6.21.2-fix-length-error.patch
@@ -0,0 +1,17 @@
+From: Kay Thomas <kaythomas@pm.me>
+Date: Sat Mar 30 02:14:43 2024 -0400
+
+Fix length_error
+
+diff --git a/src/backend/opencl/runners/OclRyoRunner.cpp b/src/backend/opencl/runners/OclRyoRunner.cpp
+index eff7f392..56edf1a4 100644
+--- a/src/backend/opencl/runners/OclRyoRunner.cpp
++++ b/src/backend/opencl/runners/OclRyoRunner.cpp
+@@ -34,6 +34,7 @@
+ #include "base/io/log/Log.h"
+ #include "base/net/stratum/Job.h"
+ #include "crypto/cn/CnAlgo.h"
++#include <stdexcept>
+ 
+ 
+ xmrig::OclRyoRunner::OclRyoRunner(size_t index, const OclLaunchData &data) : OclBaseRunner(index, data)
diff --git a/net-misc/xmrig-mo/xmrig-mo-6.21.2.ebuild b/net-misc/xmrig-mo/xmrig-mo-6.21.2.ebuild
index 776fee69e2..828e71adeb 100644
--- a/net-misc/xmrig-mo/xmrig-mo-6.21.2.ebuild
+++ b/net-misc/xmrig-mo/xmrig-mo-6.21.2.ebuild
@@ -29,6 +29,7 @@ RDEPEND="
 
 PATCHES=(
 	"${FILESDIR}"/${PN}-6.12.2-nonotls.patch
+	"${FILESDIR}"/${PN}-6.21.2-fix-length-error.patch
 )
 
 S="${WORKDIR}/xmrig-${PV}-${MO_PV}"