Re: [ietf-smtp] CC'ing ticket systems

Valdis Kl ē tnieks <> Thu, 09 July 2020 22:52 UTC

Return-Path: <>
Received: from localhost (localhost []) by (Postfix) with ESMTP id BA8023A095D for <>; Thu, 9 Jul 2020 15:52:27 -0700 (PDT)
X-Virus-Scanned: amavisd-new at
X-Spam-Flag: NO
X-Spam-Score: -1.9
X-Spam-Status: No, score=-1.9 tagged_above=-999 required=5 tests=[BAYES_00=-1.9, SPF_HELO_NONE=0.001, SPF_PASS=-0.001] autolearn=ham autolearn_force=no
Received: from ([]) by localhost ( []) (amavisd-new, port 10024) with ESMTP id X_uDQzcV7BiM for <>; Thu, 9 Jul 2020 15:52:25 -0700 (PDT)
Received: from ( [IPv6:2607:b400:92:8300:0:c6:2117:b0e]) (using TLSv1.2 with cipher ECDHE-RSA-AES256-GCM-SHA384 (256/256 bits)) (No client certificate requested) by (Postfix) with ESMTPS id 849643A095C for <>; Thu, 9 Jul 2020 15:52:25 -0700 (PDT)
Received: from ( [IPv6:2607:b400:92:8400:0:90:e077:bf22]) by (8.14.4/8.14.4) with ESMTP id 069MqNMO030998 for <>; Thu, 9 Jul 2020 18:52:24 -0400
Received: from ( []) by (8.14.7/8.14.7) with ESMTP id 069MqI5W019134 for <>; Thu, 9 Jul 2020 18:52:23 -0400
Received: by with SMTP id q6so2960605qke.21 for <>; Thu, 09 Jul 2020 15:52:23 -0700 (PDT)
X-Google-DKIM-Signature: v=1; a=rsa-sha256; c=relaxed/relaxed;; s=20161025; h=x-gm-message-state:sender:from:to:cc:subject:in-reply-to:references :mime-version:content-transfer-encoding:date:message-id; bh=E99c3YwEG7LjBVH/tILs2yTAaI3m76XH4xsIYZQifXg=; b=QhjK6hMYJPQ6idDt7eKMQWh+fm27maJqOVAPpUwjwowp3mmSkU9LTeMqSVJbPwqODr 8r6pWIRselw37YeOH2VFq5elyHVS/L+J67NLx5Qa3wQPzfDL49sW+LUnTu1xgmSDSZ0p BsgXppb6of1qXYX4g8ggPiXE85NR+CW1X34y+rQ1pgdQye9x4J8z1cRKRVcBDT8WhFi8 fdyafKYYS+ggosxgWXH474klTy6IUx8Sturg+BTsaVR9hI/ia68DjmKImjCXFU4NXuCE gm1msQOuMRWuWJzq+vZB7ZYteWpowNxgFsbe8/6jf+15ynxEeUCEVCLlPA1YaqqGdabz Yjew==
X-Gm-Message-State: AOAM532kUb3cGiWgUTjz3Co76bK6GJYbAdsaYebW0zYEbDnGOdUM/bN8 lH6KmrHI4/XqZboQ237G60crYUifsD5BJx37JAaYbdima+ypipCU3YqjrtP6pE+tPCboYj1Newo bcuQZ4cKmD5FUw1dQdvi3cA==
X-Received: by 2002:ac8:44d5:: with SMTP id b21mr29306453qto.261.1594335137874; Thu, 09 Jul 2020 15:52:17 -0700 (PDT)
X-Google-Smtp-Source: ABdhPJwLQqRAPz5+2V0Fi4ce3BuV8ZpfNrGG/t02ksy+/jEevvlzlcqKlLGQ8UH0CpQo4jShlS6WiQ==
X-Received: by 2002:ac8:44d5:: with SMTP id b21mr29306433qto.261.1594335137469; Thu, 09 Jul 2020 15:52:17 -0700 (PDT)
Received: from turing-police ([2601:5c0:c001:c9e1::359]) by with ESMTPSA id v12sm5833415qtj.32.2020. (version=TLS1_3 cipher=TLS_AES_256_GCM_SHA384 bits=256/256); Thu, 09 Jul 2020 15:52:15 -0700 (PDT)
Sender: Valdis Kletnieks <>
From: "Valdis Kl=?utf-8?Q?=c4=93?=tnieks" <>
X-Google-Original-From: "Valdis Kl=?utf-8?Q?=c4=93?=tnieks" <>
X-Mailer: exmh version 2.9.0 11/07/2018 with nmh-1.7+dev
To: "John Levine" <>
In-Reply-To: <20200708004900.C6C221C6773B@ary.qy>
References: <20200708004900.C6C221C6773B@ary.qy>
Mime-Version: 1.0
Content-Type: multipart/signed; boundary="==_Exmh_1594335134_102792P"; micalg=pgp-sha1; protocol="application/pgp-signature"
Content-Transfer-Encoding: 7bit
Date: Thu, 09 Jul 2020 18:52:15 -0400
Message-ID: <111500.1594335135@turing-police>
Archived-At: <>
Subject: Re: [ietf-smtp] CC'ing ticket systems
X-Mailman-Version: 2.1.29
Precedence: list
List-Id: "Discussion of issues related to Simple Mail Transfer Protocol \(SMTP\) \[RFC 821, RFC 2821, RFC 5321\]" <>
List-Unsubscribe: <>, <>
List-Archive: <>
List-Post: <>
List-Help: <>
List-Subscribe: <>, <>
X-List-Received-Date: Thu, 09 Jul 2020 22:52:28 -0000

On 07 Jul 2020 20:49:00 -0400, "John Levine" said:

> If I were trying to solve it, I would start with a variation on the
> way mailing list subject tags work, adding the tag if it's not there
> but leaving the subject line alone if it is.

The problem is that many MTA's *already* screw around with the Subject: line to
jam in the listname (because apparently some people *still* can't filter based
on headers other than Subject:) or "this was from outside the organization and
might be a phish" or other nonsense...

<insert .wav of 'Dueling Banjos" here>

Two headers seen on the Educause Security list:

Subject: Re: [SECURITY] [Ext] Re: [SECURITY] [EXTERNAL] Re: [SECURITY]  [EXTERNAL] Re: [SECURITY] [External] [SECURITY] Duo/2FA exemption policies

Subject: Re: [SECURITY] [BULK]  Re: [SECURITY] [BULK]  Re: [SECURITY]  [EXTERNAL] Re: [SECURITY] [BULK]  Re: [SECURITY] Microsoft Defender ATP

At which point, if your MUA doesn't thread based on References: or
In-Reply-To:, you're totally screwed because the meaningful part of the
header is now 2 feet to the right of your screen....

I despair of being able to write an RFC on the topic that won't result
in at least a half dozen organizations Getting It Totally Wrong.