diff --git a/test/kafka/kafka-client-loadtest/Dockerfile.loadtest b/test/kafka/kafka-client-loadtest/Dockerfile.loadtest
index 25aa4ae41..b16bdb9c0 100644
--- a/test/kafka/kafka-client-loadtest/Dockerfile.loadtest
+++ b/test/kafka/kafka-client-loadtest/Dockerfile.loadtest
@@ -17,16 +17,18 @@ COPY test/kafka/kafka-client-loadtest/ ./
 RUN CGO_ENABLED=0 GOOS=linux go build -o /kafka-loadtest ./cmd/loadtest
 
 # Stage 2: Runtime
-FROM ubuntu:22.04
+# Use alpine so we don't depend on Ubuntu apt mirrors, which intermittently
+# refuse connections from GitHub Actions runners and fail the CI build.
+# All runtime dependencies we need (ca-certificates, curl, jq, bash, nc)
+# are in the Alpine main repo.
+FROM alpine:3.20
 
-# Install runtime dependencies
-RUN apt-get update && apt-get install -y \
+RUN apk add --no-cache \
     ca-certificates \
     curl \
     jq \
     bash \
-    netcat \
-    && rm -rf /var/lib/apt/lists/*
+    netcat-openbsd
 
 # Copy built binary from builder stage
 COPY --from=builder /kafka-loadtest /usr/local/bin/kafka-loadtest
diff --git a/test/kafka/kafka-client-loadtest/Dockerfile.seektest b/test/kafka/kafka-client-loadtest/Dockerfile.seektest
index 5ce9d9602..b6b9e6d98 100644
--- a/test/kafka/kafka-client-loadtest/Dockerfile.seektest
+++ b/test/kafka/kafka-client-loadtest/Dockerfile.seektest
@@ -1,7 +1,8 @@
-FROM openjdk:11-jdk-slim
-
-# Install Maven
-RUN apt-get update && apt-get install -y maven && rm -rf /var/lib/apt/lists/*
+# Use the official Eclipse Temurin + Maven image so we don't depend on
+# Debian apt mirrors, which intermittently refuse connections from
+# GitHub Actions runners and fail the CI build. This image already has
+# JDK 11 and Maven installed.
+FROM maven:3.9-eclipse-temurin-11
 
 WORKDIR /app