diff --git a/Dockerfile.updater-core b/Dockerfile.updater-core
index 1992a53597..2ba9f75882 100644
--- a/Dockerfile.updater-core
+++ b/Dockerfile.updater-core
@@ -111,7 +111,7 @@ 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 b67a7efee7..a38f22e836 100644
--- a/Gemfile.lock
+++ b/Gemfile.lock
@@ -387,4 +387,4 @@ DEPENDENCIES
   webrick (>= 1.7)
 
 BUNDLED WITH
-   2.5.3
+   2.5.5
diff --git a/updater/Gemfile.lock b/updater/Gemfile.lock
index 6372f13052..2947f23b08 100644
--- a/updater/Gemfile.lock
+++ b/updater/Gemfile.lock
@@ -405,4 +405,4 @@ DEPENDENCIES
   webrick (>= 1.7)
 
 BUNDLED WITH
-   2.5.3
+   2.5.5