oss-sec mailing list archives
Re: [CVE-2015-0839] hp-plugin binary driver verification
From: Daniel Kahn Gillmor <dkg () fifthhorseman net>
Date: Sun, 31 May 2015 21:52:45 -0400
On Fri 2015-05-29 09:00:35 -0400, Enrico Zini wrote:
I was forced to run hp-plugin to download a binary driver for the new printer, and I noticed this bit: Downloading plug-in from: Receiving digital keys: /usr/bin/gpg --homedir /home/enrico/.hplip/.gnupg --no-permission-warning --keyserver pgp.mit.edu --recv-keys 0xA59047B9 Creating directory plugin_tmp Verifying archive integrity... All good. The use of a short key ID worries me, because it is now trivial to generate keys with arbitrary key IDs, and gpg --recv-keys will happily download all those it finds. Also, pgp.mit.edu is a keyserver where everyone can upload arbitrary keys. You can run "gpg --recv 70096AD1" to play with multiple keys having the same key ID. I assume hp-plugin is open to downloading and verifying plugins signed by any key that one can verify that have that short key ID, and that with that and some fiddling with DNS one can cause systems running hp-plugin to download and run malicious code. A quick fix would be to use the full fingerprint instead of the key id.
A better quick fix would be to ship the authoritative key in hplip directly, and avoid all interaction with the keyservers. --dkg
Current thread:
- [CVE-2015-0839] hp-plugin binary driver verification Enrico Zini (May 29)
- Re: [CVE-2015-0839] hp-plugin binary driver verification Daniel Kahn Gillmor (May 31)