diff --git a/iso/builder/config/hooks/normal/9998-strip-xattrs.hook.chroot b/iso/builder/config/hooks/normal/9998-strip-xattrs.hook.chroot
new file mode 100755
index 0000000..d46b110
--- /dev/null
+++ b/iso/builder/config/hooks/normal/9998-strip-xattrs.hook.chroot
@@ -0,0 +1,37 @@
+#!/usr/bin/env python3
+# 9998-strip-xattrs.hook.chroot
+#
+# mksquashfs 4.5.1 (Debian bookworm) writes a non-INVALID xattr_id_table_start
+# even with -no-xattrs when the source tree contains POSIX ACL xattrs set by
+# dpkg/install-time.  Linux 6.1 squashfs driver then fails with
+# "unable to read xattr id index table" and aborts the mount.
+#
+# Strip all xattrs from the live chroot before mksquashfs sees the tree so the
+# resulting squashfs has SQUASHFS_INVALID_BLK in xattr_id_table_start.
+
+import os
+
+def strip(path):
+    try:
+        for attr in os.listxattr(path, follow_symlinks=False):
+            try:
+                os.removexattr(path, attr, follow_symlinks=False)
+            except OSError:
+                pass
+    except OSError:
+        pass
+
+removed = 0
+for root, dirs, files in os.walk('/', topdown=True, followlinks=False):
+    for name in dirs + files:
+        p = os.path.join(root, name)
+        try:
+            attrs = os.listxattr(p, follow_symlinks=False)
+            if attrs:
+                strip(p)
+                removed += len(attrs)
+        except OSError:
+            pass
+    strip(root)
+
+print(f"9998-strip-xattrs: removed xattrs from {removed} entries")