[If possible, please preserve the 745553-forwarded address in any replies.]
This bug was filed recently, and I suspect it might be something you'd like to discuss upstream. Thanks Daniel Kahn Gillmor <d...@fifthhorseman.net> writes: > Package: emacs24-el > Version: 24.3+1-2 > Severity: normal > > Hi emacs maintainers! > > in > > /usr/share/emacs/24.3/lisp/gnus/mml2015.el.gz > > i see this variable definition: > > (defcustom mml2015-always-trust t > "If t, GnuPG skip key validation on encryption." > :group 'mime-security > :type 'boolean) > > This is a security risk for users of encrypted mail. i believe it > should be set to nil by default. > > Here's why: > > Consider Alice, who has OpenPGP certificates for "Bob > <b...@example.org>" and "Carol <ca...@example.org>" in her keyring (in > that order). She has certified them both, so there is one valid > primary key for b...@example.org and one valid primary key for > al...@example.org. > > Bob turns evil (or maybe his key is compromised) and he adds a new > User ID: "Bob <ca...@example.org>" to his OpenPGP cert. He publishes > the update to the keyservers. > > Alice, following best practices, updates her keyring from the > keyservers regularly. > > Alice's keyring now has two certs that have a "ca...@example.org" user > ID in them. One of them is valid, and the other one is not. > > Alice now composes a message to "Carol <ca...@example.org>" and marks > it with: > > <#secure method=pgpmime mode=signencrypt> > > As the message goes out, mml-mode just passes the e-mail address > ca...@example.org to gpg to encrypt the message body, and gpg uses the > e-mail address to select a key. Since Bob's key is first in the > keyring, it is the one that will be used. > > Bob then sneaks a peak at Carol's e-mail (maybe they're delivered to the > same server, or he has a machine on the same network), catches the > message in transit, and can decrypt the content, violating Alice's > message confidentiality expectations. > > Please set mml2015-always-trust to default to "nil" instead of "t". > > --dkg > > -- System Information: > Debian Release: jessie/sid > APT prefers testing > APT policy: (500, 'testing'), (200, 'unstable'), (1, 'experimental') > Architecture: amd64 (x86_64) > Foreign Architectures: i386 > > Kernel: Linux 3.13-1-amd64 (SMP w/4 CPU cores) > Locale: LANG=en_US.UTF-8, LC_CTYPE=en_US.UTF-8 (charmap=UTF-8) > Shell: /bin/sh linked to /bin/dash > > Versions of packages emacs24-el depends on: > ii emacs24-common 24.3+1-2 > > emacs24-el recommends no packages. > > emacs24-el suggests no packages. > > -- debconf-show failed > -- Rob Browning rlb @defaultvalue.org and @debian.org GPG as of 2011-07-10 E6A9 DA3C C9FD 1FF8 C676 D2C4 C0F0 39E9 ED1B 597A GPG as of 2002-11-03 14DD 432F AE39 534D B592 F9A0 25C8 D377 8C7E 73A4 -- To UNSUBSCRIBE, email to debian-bugs-dist-requ...@lists.debian.org with a subject of "unsubscribe". Trouble? Contact listmas...@lists.debian.org
