oss-sec mailing list archives
Re: Re: New SMTP smuggling attack
From: Erik Auerswald <auerswal () unix-ag uni-kl de>
Date: Fri, 22 Dec 2023 16:04:38 +0100
Hi, On Fri, Dec 22, 2023 at 01:11:37PM +0100, Marcus Meissner wrote:
On Fri, Dec 22, 2023 at 11:09:49AM +0000, Stuart Henderson wrote:On 2023/12/22 11:46, Marcus Meissner wrote:FWIW as no CVEs were to be found yet, I filed a CVE request for Postfix now. Not sure if we need it for others like sendmail too, as that is also referenced by the security researchers.
I'd think that sendmail should have a CVE, too, or there could be one CVE pertaining to both Postfix and sendmail, because SEC Consult write in their blog post: "After testing some popular e-mail software in their default configuration, it turned out that Postfix and Sendmail fulfil the requirements, are affected and can be smuggled to." As such I'd say that both Postfix and sendmail are known to be vulnerable.
I'm a little confused by sec-consult's process here. They identify a problem affecting various pieces of software including some very widely deployed open source software, go to the trouble of doing a coordinated disclosure, but only do that with...looking at their timeline... gmx, microsoft and cisco?Yes its weird. I was also confused and actually only spotted the OSS software being affected on third read over their page. They also reference CERT and VINCE, but at least SUSE was not pulled into the VINCE issue if there was any. (as CERT has not published anything I am not sure there was any besides the Cisco disclosure).
According to the timeline, they involved CERT/CC and VINCE in August: 2023-08-17: Contacting CERT Coordination Center (CERT/CC) for further discussion with Cisco ... 2023-09-13: CERT/CC accepts the case ... 2023-11-29: CERT/CC allows public release of SMTP smuggling, since no software vulnerabilities were identified ("it's not a bug, it's a feature") ... 2023-12-18: Release date of blog post The first timeline entry omits a bit from the text, i.e., VINCE: "we contacted CERT/CC on 17th August to get some help for further discussion with Cisco and involve other potentially affected vendors (such as sendmail) through the VINCE communication platform."
Also postfix timeline starts 4 days ago only. https://www.mail-archive.com/postfix-announce () postfix org/msg00090.html
This is three days after the SEC Consult blog post. My personal interpretation is as follows: * SEC Consult concentrated on the big email platforms, because of the potential impact. * They informed platforms that could be used to perform the attack against vulnerable targets. * They informed Cisco since they used an affected Cisco product and could thus be targeted (even though for Cisco this is not a vulnerability, but a feature). * They involved CERT/CC and VINCE, probably with the assumption that this would result in identifying and informing affected vendors and projects. * The CERT/CC and VINCE involvement resulted in "there is no vulnerability". * SEC Consult publish their findings. Now, others (including me) see this as a vulnerability affecting at least some open source email servers. SNAFU. Cheers, Erik
Current thread:
- New SMTP smuggling attack Marcus Meissner (Dec 21)
- Re: New SMTP smuggling attack Claus Assmann (Dec 21)
- Re: Re: New SMTP smuggling attack Marcus Meissner (Dec 22)
- Re: Re: New SMTP smuggling attack Stuart Henderson (Dec 22)
- Re: Re: New SMTP smuggling attack Marcus Meissner (Dec 22)
- Re: Re: New SMTP smuggling attack Erik Auerswald (Dec 22)
- Re: Re: New SMTP smuggling attack Rodrigo Freire (Dec 22)
- Re: Re: New SMTP smuggling attack Alexander E. Patrakov (Dec 22)
- Re: Re: New SMTP smuggling attack Erik Auerswald (Dec 22)
- Re: Re: New SMTP smuggling attack Stuart D Gathman (Dec 22)
- Re: Re: New SMTP smuggling attack Harry Sintonen (Dec 22)
- Re: Re: New SMTP smuggling attack Marcus Meissner (Dec 22)
- Re: New SMTP smuggling attack Claus Assmann (Dec 21)
- Re: Re: New SMTP smuggling attack Bjoern Franke (Dec 22)
- Re: Re: New SMTP smuggling attack Valtteri Vuorikoski (Dec 23)
- Re: Re: New SMTP smuggling attack Marcus Meissner (Dec 24)
- Re: Re: New SMTP smuggling attack kai (Dec 25)
- Re: New SMTP smuggling attack Claus Assmann (Dec 26)