From mboxrd@z Thu Jan 1 00:00:00 1970 Return-Path: Received: from ffbox0-bg.mplayerhq.hu (ffbox0-bg.ffmpeg.org [79.124.17.100]) by master.gitmailbox.com (Postfix) with ESMTPS id B11B94B9B0 for ; Thu, 23 Jan 2025 00:11:45 +0000 (UTC) Received: from [127.0.1.1] (localhost [127.0.0.1]) by ffbox0-bg.mplayerhq.hu (Postfix) with ESMTP id 1926568B9FD; Thu, 23 Jan 2025 02:11:42 +0200 (EET) Received: from relay6-d.mail.gandi.net (relay6-d.mail.gandi.net [217.70.183.198]) by ffbox0-bg.mplayerhq.hu (Postfix) with ESMTPS id DCB3768B634 for ; Thu, 23 Jan 2025 02:11:35 +0200 (EET) Received: by mail.gandi.net (Postfix) with ESMTPSA id 3AC4DC0003 for ; Thu, 23 Jan 2025 00:11:34 +0000 (UTC) DKIM-Signature: v=1; a=rsa-sha256; c=relaxed/relaxed; d=niedermayer.cc; s=gm1; t=1737591095; h=from:from:reply-to:subject:subject:date:date:message-id:message-id: to:to:cc:mime-version:mime-version:content-type:content-type: in-reply-to:in-reply-to:references:references; bh=kC1lR3veaEHfP2Cfq3SfsP03Hb1dFTxcE9KBJB19GGw=; b=Pbu0rmzMUP76LzwhimTBZEPczSHeLR7pRCD2JBeMYTyp468j28bo7qJRgqInwNoGFJWfUT hb6if28070gaY/2WLnj2G8+bPJvG7x82Iy7vtswuHPbl1UOQ1BrZ3dYlmRmXH10EdrhI1p iXup+GMHyXqwW/8UCzmLB+UBye2jhLiAl08hppflb3Nl6DXaMmQPH391ag08XQjeoJZ31I p1K7pCGR/V4HqQIlDWHpV00JzhUVPajHBRJz4vxeI5JmMiw3KO1hvw7wexpwGVFo2BUbLr PaceUmzAEoBw0VoJBc67eNKPj3/gknzb8QaNzGm0H5RHZTa2xDZT+tahj4SNiQ== Date: Thu, 23 Jan 2025 01:11:34 +0100 From: Michael Niedermayer To: FFmpeg development discussions and patches Message-ID: <20250123001134.GA4991@pb2> References: <20250122203609.1796499-1-michael@niedermayer.cc> <20250122203609.1796499-2-michael@niedermayer.cc> MIME-Version: 1.0 In-Reply-To: X-GND-Sasl: michael@niedermayer.cc Subject: Re: [FFmpeg-devel] [PATCH 2/2] avformat/hls: Be more picky on extensions X-BeenThere: ffmpeg-devel@ffmpeg.org X-Mailman-Version: 2.1.29 Precedence: list List-Id: FFmpeg development discussions and patches List-Unsubscribe: , List-Archive: List-Post: List-Help: List-Subscribe: , Reply-To: FFmpeg development discussions and patches Content-Type: multipart/mixed; boundary="===============2110909788953328396==" Errors-To: ffmpeg-devel-bounces@ffmpeg.org Sender: "ffmpeg-devel" Archived-At: List-Archive: List-Post: --===============2110909788953328396== Content-Type: multipart/signed; micalg=pgp-sha512; protocol="application/pgp-signature"; boundary="kDJ/jHvtI1xBUwe+" Content-Disposition: inline --kDJ/jHvtI1xBUwe+ Content-Type: text/plain; charset=us-ascii Content-Disposition: inline Content-Transfer-Encoding: quoted-printable Hi Kieran On Wed, Jan 22, 2025 at 10:47:52PM +0000, Kieran Kunhya via ffmpeg-devel wr= ote: > On Wed, 22 Jan 2025, 20:36 Michael Niedermayer, > wrote: >=20 > > This blocks disallowed extensions from probing > > It also requires all available segments to have matching extensions to = the > > format > > mpegts is treated independent of the extension > > >=20 > Potentially this is a stupid question but what stops an attacker from > faking the extension? How would he fake the extension ? The attacker generally wants to access a sensitive file, maybe one in /etc or maybe .ssh with something like the tty demuxer / ansi decoder lets pick /etc/passwd as a specific example that file does not have an extension compatible with the tty demuxer and we assume that the attacker cannot create links on the target because if he can he likely can also just read the file directly This new patch should require every file now to have the appropriate extension before reading it with that demuxer. Before this patch you could trigger a demuxer to be probed and have it be used on another file If you see a way to bypass this still, please tell me thx [...] --=20 Michael GnuPG fingerprint: 9FF2128B147EF6730BADF133611EC787040B0FAB Whats the most studid thing your enemy could do ? Blow himself up Whats the most studid thing you could do ? Give up your rights and freedom because your enemy blew himself up. --kDJ/jHvtI1xBUwe+ Content-Type: application/pgp-signature; name="signature.asc" -----BEGIN PGP SIGNATURE----- iF0EABEKAB0WIQSf8hKLFH72cwut8TNhHseHBAsPqwUCZ5GJMgAKCRBhHseHBAsP q5M4AJ0dYgWnjhCIcQZqCDdk4V3B7uDDsgCffJhYLTkGGq/P54T4zA+kXt6vk5o= =SpzR -----END PGP SIGNATURE----- --kDJ/jHvtI1xBUwe+-- --===============2110909788953328396== Content-Type: text/plain; charset="us-ascii" MIME-Version: 1.0 Content-Transfer-Encoding: 7bit Content-Disposition: inline _______________________________________________ ffmpeg-devel mailing list ffmpeg-devel@ffmpeg.org https://ffmpeg.org/mailman/listinfo/ffmpeg-devel To unsubscribe, visit link above, or email ffmpeg-devel-request@ffmpeg.org with subject "unsubscribe". --===============2110909788953328396==--