Issue #22638: SSLv3 is now disabled throughout the standard library.

It can still be enabled by instantiating a SSLContext manually.

Lib/ssl.py

@@ -454,6 +454,9 @@ def _create_stdlib_context(protocol=PROTOCOL_SSLv23, *, cert_reqs=None,
     context = SSLContext(protocol)
     # SSLv2 considered harmful.
     context.options |= OP_NO_SSLv2
+    # SSLv3 has problematic security and is only required for really old
+    # clients such as IE6 on Windows XP
+    context.options |= OP_NO_SSLv3
 
     if cert_reqs is not None:
         context.verify_mode = cert_reqs

Misc/NEWS

@@ -178,6 +178,9 @@ Core and Builtins
 Library
 -------
 
+- Issue #22638: SSLv3 is now disabled throughout the standard library.
+  It can still be enabled by instantiating a SSLContext manually.
+
 - Issue #22641: In asyncio, the default SSL context for client connections
   is now created using ssl.create_default_context(), for stronger security.