diff --git a/.github/workflows/main.yml b/.github/workflows/main.yml
index 8dbf64f0..15802bec 100644
--- a/.github/workflows/main.yml
+++ b/.github/workflows/main.yml
@@ -27,6 +27,7 @@ jobs:
         run: make build_customizable
 
       - name: Log in to the Container registry
+        if: ${{ github.event.pull_request.merged && github.ref == 'refs/heads/master' }}
         uses: docker/login-action@f054a8b539a109f9f41c372932f1ae047eff08c9
         with:
           registry: ghcr.io
@@ -34,6 +35,7 @@ jobs:
           password: ${{ secrets.GITHUB_TOKEN }}
 
       - name: Push to github container registry
+        if: ${{ github.event.pull_request.merged && github.ref == 'refs/heads/master' }}
         run: make release_customizable
 
   build-ruby27:
@@ -52,6 +54,7 @@ jobs:
         run: make build_ruby27
 
       - name: Log in to the Container registry
+        if: ${{ github.event.pull_request.merged && github.ref == 'refs/heads/master' }}
         uses: docker/login-action@f054a8b539a109f9f41c372932f1ae047eff08c9
         with:
           registry: ghcr.io
@@ -59,6 +62,7 @@ jobs:
           password: ${{ secrets.GITHUB_TOKEN }}
 
       - name: Push to github container registry
+        if: ${{ github.event.pull_request.merged && github.ref == 'refs/heads/master' }}
         run: make release_ruby27
 
   build-ruby30:
@@ -77,6 +81,7 @@ jobs:
         run: make build_ruby30
 
       - name: Log in to the Container registry
+        if: ${{ github.event.pull_request.merged && github.ref == 'refs/heads/master' }}
         uses: docker/login-action@f054a8b539a109f9f41c372932f1ae047eff08c9
         with:
           registry: ghcr.io
@@ -84,6 +89,7 @@ jobs:
           password: ${{ secrets.GITHUB_TOKEN }}
 
       - name: Push to github container registry
+        if: ${{ github.event.pull_request.merged && github.ref == 'refs/heads/master' }}
         run: make release_ruby30
 
   build-ruby31:
@@ -102,6 +108,7 @@ jobs:
         run: make build_ruby31
 
       - name: Log in to the Container registry
+        if: ${{ github.event.pull_request.merged && github.ref == 'refs/heads/master' }}
         uses: docker/login-action@f054a8b539a109f9f41c372932f1ae047eff08c9
         with:
           registry: ghcr.io
@@ -109,6 +116,7 @@ jobs:
           password: ${{ secrets.GITHUB_TOKEN }}
 
       - name: Push to github container registry
+        if: ${{ github.event.pull_request.merged && github.ref == 'refs/heads/master' }}
         run: make release_ruby31
 
   build-ruby32:
@@ -127,6 +135,7 @@ jobs:
         run: make build_ruby32
 
       - name: Log in to the Container registry
+        if: ${{ github.event.pull_request.merged && github.ref == 'refs/heads/master' }}
         uses: docker/login-action@f054a8b539a109f9f41c372932f1ae047eff08c9
         with:
           registry: ghcr.io
@@ -134,6 +143,7 @@ jobs:
           password: ${{ secrets.GITHUB_TOKEN }}
 
       - name: Push to github container registry
+        if: ${{ github.event.pull_request.merged && github.ref == 'refs/heads/master' }}
         run: make release_ruby32
 
   build-jruby93:
@@ -152,6 +162,7 @@ jobs:
         run: make build_jruby93
 
       - name: Log in to the Container registry
+        if: ${{ github.event.pull_request.merged && github.ref == 'refs/heads/master' }}
         uses: docker/login-action@f054a8b539a109f9f41c372932f1ae047eff08c9
         with:
           registry: ghcr.io
@@ -159,6 +170,7 @@ jobs:
           password: ${{ secrets.GITHUB_TOKEN }}
 
       - name: Push to github container registry
+        if: ${{ github.event.pull_request.merged && github.ref == 'refs/heads/master' }}
         run: make release_jruby93
 
   build-jruby94:
@@ -177,6 +189,7 @@ jobs:
         run: make build_jruby94
 
       - name: Log in to the Container registry
+        if: ${{ github.event.pull_request.merged && github.ref == 'refs/heads/master' }}
         uses: docker/login-action@f054a8b539a109f9f41c372932f1ae047eff08c9
         with:
           registry: ghcr.io
@@ -184,6 +197,7 @@ jobs:
           password: ${{ secrets.GITHUB_TOKEN }}
 
       - name: Push to github container registry
+        if: ${{ github.event.pull_request.merged && github.ref == 'refs/heads/master' }}
         run: make release_jruby94
 
   build-nodejs:
@@ -202,6 +216,7 @@ jobs:
         run: make build_nodejs
 
       - name: Log in to the Container registry
+        if: ${{ github.event.pull_request.merged && github.ref == 'refs/heads/master' }}
         uses: docker/login-action@f054a8b539a109f9f41c372932f1ae047eff08c9
         with:
           registry: ghcr.io
@@ -209,6 +224,7 @@ jobs:
           password: ${{ secrets.GITHUB_TOKEN }}
 
       - name: Push to github container registry
+        if: ${{ github.event.pull_request.merged && github.ref == 'refs/heads/master' }}
         run: make release_nodejs
 
   build-full:
@@ -227,6 +243,7 @@ jobs:
         run: make build_full
 
       - name: Log in to the Container registry
+        if: ${{ github.event.pull_request.merged && github.ref == 'refs/heads/master' }}
         uses: docker/login-action@f054a8b539a109f9f41c372932f1ae047eff08c9
         with:
           registry: ghcr.io
@@ -234,4 +251,5 @@ jobs:
           password: ${{ secrets.GITHUB_TOKEN }}
 
       - name: Push to github container registry
+        if: ${{ github.event.pull_request.merged && github.ref == 'refs/heads/master' }}
         run: make release_full
diff --git a/CHANGELOG.md b/CHANGELOG.md
index 456f63de..c20d3eb9 100644
--- a/CHANGELOG.md
+++ b/CHANGELOG.md
@@ -1,6 +1,8 @@
 ## not released
  * Compile all CRuby versions from source to ensure uniformity and YJIT capability in versions 3.1+
  * Use Ruby 3.2.x by default
+ * Upgraded to JRuby 9.3.10.0
+ * Upgraded to JRuby 9.4.3.0
 
 ## 2.5.1 (release date: 2023-06-14)
  * Upgraded to Phusion Passenger 6.0.18 (from 6.0.17).
diff --git a/README.md b/README.md
index d4b4290c..e952ae9c 100644
--- a/README.md
+++ b/README.md
@@ -94,7 +94,7 @@ Basics (learn more at [baseimage-docker](http://phusion.github.io/baseimage-dock
 
 Language support:
 
- * Ruby 2.7.8, 3.0.6, 3.1.4, 3.2.2 and JRuby 9.3.9.0 and 9.4.0.0.
+ * Ruby 2.7.8, 3.0.6, 3.1.4, 3.2.2 and JRuby 9.3.10.0 and 9.4.3.0.
    * RVM is used to manage Ruby versions. [Why RVM?](#why_rvm)
    * 3.2.2 is configured as the default.
    * JRuby is installed from source, but we register an APT entry for it.
@@ -438,10 +438,10 @@ RUN bash -lc 'rvm --default use ruby-3.0.6'
 RUN bash -lc 'rvm --default use ruby-3.1.4'
 # Ruby 3.2.2
 RUN bash -lc 'rvm --default use ruby-3.2.2'
-# JRuby 9.3.9.0
-RUN bash -lc 'rvm --default use jruby-9.3.9.0'
-# JRuby 9.4.0.0
-RUN bash -lc 'rvm --default use jruby-9.4.0.0'
+# JRuby 9.3.10.0
+RUN bash -lc 'rvm --default use jruby-9.3.10.0'
+# JRuby 9.4.3.0
+RUN bash -lc 'rvm --default use jruby-9.4.3.0'
 ```
 
 Learn more: [RVM: Setting the default Ruby](https://rvm.io/rubies/default).
diff --git a/image/jruby-9.3.9.0.sh b/image/jruby-9.3.10.0.sh
similarity index 100%
rename from image/jruby-9.3.9.0.sh
rename to image/jruby-9.3.10.0.sh
diff --git a/image/jruby-9.4.0.0.sh b/image/jruby-9.4.3.0.sh
similarity index 100%
rename from image/jruby-9.4.0.0.sh
rename to image/jruby-9.4.3.0.sh