diff --git a/Dockerfile b/Dockerfile
index ef6969692c..75d76271d2 100644
--- a/Dockerfile
+++ b/Dockerfile
@@ -19,7 +19,7 @@
 # change.
 
 
-FROM ubuntu:24.04 AS dark-base
+FROM ubuntu:25.10 AS dark-base
 
 ENV FORCE_BUILD=8
 
diff --git a/Dockerfile.build-base b/Dockerfile.build-base
index 6746d1a66b..39a5c9a073 100644
--- a/Dockerfile.build-base
+++ b/Dockerfile.build-base
@@ -8,7 +8,7 @@
 # Carries clang and cross sysroots because ilc links through a C compiler and
 # gcc can't cross-target, so one x64 runner covers every linux artifact. macOS
 # still needs a Mac.
-FROM ubuntu:20.04
+FROM ubuntu:25.10
 
 ENV DEBIAN_FRONTEND=noninteractive