Issue #13885: CVE-2011-3389: the _ssl module would always disable the CBC IV attack countermeasure.
diff --git a/Modules/_ssl.c b/Modules/_ssl.c
index 4619cda..46f71e8 100644
--- a/Modules/_ssl.c
+++ b/Modules/_ssl.c
@@ -357,7 +357,8 @@
     }
 
     /* ssl compatibility */
-    SSL_CTX_set_options(self->ctx, SSL_OP_ALL);
+    SSL_CTX_set_options(self->ctx,
+                        SSL_OP_ALL & ~SSL_OP_DONT_INSERT_EMPTY_FRAGMENTS);
 
     verification_mode = SSL_VERIFY_NONE;
     if (certreq == PY_SSL_CERT_OPTIONAL)