--- a/mercurial/commands.py	Fri Mar 10 07:10:19 2023 +0100
+++ b/mercurial/commands.py	Fri Mar 10 07:19:25 2023 +0100
@@ -1665,6 +1665,14 @@
         scmutil.nochangesfound(ui, repo, not base and excluded)
         return 1
 
+    # internal changeset are internal implementation details that should not
+    # leave the repository. Bundling with `hg bundle` create such risk.
+    bundled_internal = repo.revs(b"%ln and _internal()", missing)
+    if bundled_internal:
+        msg = _(b"cannot bundle internal changesets")
+        hint = _(b"%d internal changesets selected") % len(bundled_internal)
+        raise error.Abort(msg, hint=hint)
+
     if heads:
         outgoing = discovery.outgoing(
             repo, missingroots=missing, ancestorsof=heads

--- a/tests/test-bundle-phase-internal.t	Fri Mar 10 07:10:19 2023 +0100
+++ b/tests/test-bundle-phase-internal.t	Fri Mar 10 07:19:25 2023 +0100
@@ -234,3 +234,53 @@
   A a_file.txt
 
   $ cd ..
+
+Explicitly bundling the internal change
+=======================================
+
+  $ cd reference-repo
+
+try to bundle it alone explicitly
+---------------------------------
+
+We should not allow it
+
+  $ hg bundle --type v3 --exact --rev $shelved_node --hidden ../internal-01.hg
+  abort: cannot bundle internal changesets
+  (1 internal changesets selected)
+  [255]
+  $ hg debugbundle ../internal-01.hg
+  abort: $ENOENT$: '../internal-01.hg'
+  [255]
+
+try to bundle it with other, somewhat explicitly
+------------------------------------------------
+
+We should not allow it
+
+  $ hg bundle --type v3 --exact --rev 'desc(b)':: --hidden ../internal-02.hg
+  abort: cannot bundle internal changesets
+  (1 internal changesets selected)
+  [255]
+  $ hg debugbundle ../internal-02.hg
+  abort: $ENOENT$: '../internal-02.hg'
+  [255]
+
+bundle visible ancestors
+------------------------
+
+This should succeed as the standard filtering is skipping the internal change naturally
+
+  $ hg bundle --type v3 --exact --rev 'desc(b)':: ../internal-03.hg
+  2 changesets found
+  $ hg debugbundle ../internal-03.hg
+  Stream params: {Compression: BZ}
+  changegroup -- {nbchanges: 2, version: 03} (mandatory: True)
+      d2ae7f538514cd87c17547b0de4cea71fe1af9fb
+      07f0cc02c06869c81ebf33867edef30554020c0d
+  cache:rev-branch-cache -- {} (mandatory: False)
+  phase-heads -- {} (mandatory: True)
+      07f0cc02c06869c81ebf33867edef30554020c0d draft
+
+  $ cd ..
+