diff --git a/.github/workflows/docker-image.yml b/.github/workflows/docker-image.yml
index 82e6e6e..ec90f43 100644
--- a/.github/workflows/docker-image.yml
+++ b/.github/workflows/docker-image.yml
@@ -2,9 +2,9 @@ name: Docker Image CI
 
 on:
   push:
-    branches: [ master ]
+    branches: [ dev ]
   pull_request:
-    branches: [ master ]
+    branches: [ dev ]
     
   workflow_dispatch:
 
diff --git a/Dockerfile b/Dockerfile
index 13a062e..fa65c33 100644
--- a/Dockerfile
+++ b/Dockerfile
@@ -1,4 +1,4 @@
-FROM phusion/baseimage:focal-1.2.0
+FROM phusion/baseimage:jammy-1.0.4
 LABEL maintainer="skysider <skysider@163.com>"
 
 ENV DEBIAN_FRONTEND noninteractive
@@ -71,7 +71,7 @@ RUN python3 -m pip config set global.index-url http://pypi.tuna.tsinghua.edu.cn/
     pebble \
     r2pipe
 
-RUN gem install one_gadget seccomp-tools && rm -rf /var/lib/gems/*/cache/*
+RUN gem install elftools one_gadget seccomp-tools && rm -rf /var/lib/gems/*/cache/*
 
 RUN git clone --depth 1 https://github.com/pwndbg/pwndbg && \
     cd pwndbg && chmod +x setup.sh && ./setup.sh
@@ -126,8 +126,6 @@ COPY linux_server linux_server64  /ctf/
 
 RUN chmod a+x /ctf/linux_server /ctf/linux_server64
 
-ARG PWNTOOLS_VERSION
-
-RUN python3 -m pip install --no-cache-dir pwntools==${PWNTOOLS_VERSION}
+RUN python3 -m pip install --no-cache-dir pwntools
 
 CMD ["/sbin/my_init"]
diff --git a/README.md b/README.md
index 9cc0ecc..99d5ec9 100644
--- a/README.md
+++ b/README.md
@@ -1,6 +1,6 @@
 Pwndocker
 =========
-A docker environment for pwn in ctf based on **phusion/baseimage:focal-1.2.0**, which is a modified ubuntu 20.04 baseimage for docker
+A docker environment for pwn in ctf based on **phusion/baseimage:jammy-1.0.4**, which is a modified ubuntu 22.04 baseimage for docker
 
 ### Usage
 
@@ -92,6 +92,9 @@ root@pwn:/ctf/work# /glibc/2.28/64/ld-2.28.so /bin/ls -l /
 
 ### ChangeLog
 
+#### 2025-09-14
+update base image to ubuntu 22.04 and update `pwntools` version to 4.14.1
+
 #### 2023-10-22
 add `zsh` and `ohmyzsh` to docker image, update `pwntools` version to 4.11.0