use latest rustc version for rustlib
diff --git a/build/docker/ubuntu-focal/Dockerfile b/build/docker/ubuntu-focal/Dockerfile
index a29ec69..8c2cd61 100644
--- a/build/docker/ubuntu-focal/Dockerfile
+++ b/build/docker/ubuntu-focal/Dockerfile
@@ -274,7 +274,7 @@
 
 USER ${user}
 RUN `# Rust dependencies` \
-    curl https://sh.rustup.rs -sSf | sh -s -- --default-toolchain 1.65.0 -y
+    curl https://sh.rustup.rs -sSf | sh -s -- --default-toolchain 1.81.0 -y
 ENV PATH /home/${user}/.cargo/bin:$PATH
 USER root