diff --git a/src/calibre/ebooks/odt/input.py b/src/calibre/ebooks/odt/input.py
index 438e0336b7..cc8073ee37 100644
--- a/src/calibre/ebooks/odt/input.py
+++ b/src/calibre/ebooks/odt/input.py
@@ -34,7 +34,7 @@ class Extract(ODF2XHTML):
         for name in zf.namelist():
             if name.startswith('Pictures') and name not in {'Pictures', 'Pictures/'}:
                 dest = os.path.abspath(os.path.join(base, name))
-                if os.path.commonprefix([base, dest]) != dest:
+                if os.path.commonprefix([base, dest]) != base:
                     continue
                 data = zf.read(name)
                 with open(dest, 'wb') as f: