diff --git a/Dockerfile.updater-core b/Dockerfile.updater-core
index 1e79897732..dfdc8b3071 100644
--- a/Dockerfile.updater-core
+++ b/Dockerfile.updater-core
@@ -110,7 +110,7 @@ WORKDIR $DEPENDABOT_HOME/dependabot-updater
 # When bumping Bundler, need to also:
 # * Regenerate `updater/Gemfile.lock` via `BUNDLE_GEMFILE=updater/Gemfile bundle lock --update --bundler`
 # * Regenerate `Gemfile.lock` via `bundle lock --update --bundler`.
-ARG BUNDLER_V2_VERSION=2.5.3
+ARG BUNDLER_V2_VERSION=2.5.5
 
 RUN gem install bundler -v $BUNDLER_V2_VERSION --no-document && \
  rm -rf /var/lib/gems/*/cache/* && \
diff --git a/Gemfile.lock b/Gemfile.lock
index 38df85550d..0007a5f3b0 100644
--- a/Gemfile.lock
+++ b/Gemfile.lock
@@ -339,4 +339,4 @@ DEPENDENCIES
   webrick (>= 1.7)
 
 BUNDLED WITH
-   2.5.3
+   2.5.5
diff --git a/updater/Gemfile.lock b/updater/Gemfile.lock
index 76c6a8255f..335dd2d3af 100644
--- a/updater/Gemfile.lock
+++ b/updater/Gemfile.lock
@@ -388,4 +388,4 @@ DEPENDENCIES
   webrick (>= 1.7)
 
 BUNDLED WITH
-   2.5.3
+   2.5.5