Okay, since there’s so much stuff to digest here and apparently there are issues designated as wontfix by GnuPG maintainers, can someone more in the loop tell us whether using gpg signatures on git commits/tags is vulnerable? And is there any better alternative going forward? Like is signing with SSH keys considered more secure now? I certainly want to get rid of gpg from my life if I can, but I also need to make sure commits/tags bearing my name actually come from me.
I did the switch this year after getting yet another personal computer. I have 4 in total (work laptop, personal sofa laptop, Mac Mini, Linux Tower). I used Yubi keys with gpg and resident ssh keys. All is fine but the configuration needed to get it too work on all the machines. I also tend to forget the finer details and have to relearn the skills of fetching the public keys into the keychain etc. I got rid of this all by moving to 1Password ssh agent and git ssh signing. Removes a lot of headaches from my ssh setup. I still have the yubi key(s) though as a 2nd factor for certain web services. And the gpg agent is still running but only as a fallback. I will turn this off next year.
Maybe the site is overloaded. But as for the "brb, were on it!!!!" - this page had the live stream of the talk when it was happening. Hopefully they'll replace it with the recording when media.ccc.de posts it, which should be within a couple hours.
This feels pretty unsatisfying: something that’s been “considered harmful” for three decades should be deprecated and then removed in a responsible ecosystem.
(PGP/GPG are of course hamstrung by their own decision to be a Swiss Army knife/only loosely coupled to the secure operation itself. So the even more responsible thing to do is to discard them for purposes that they can’t offer security properties for, which is the vast majority of things they get used for.)
Can you provide a source this? To my understanding, the GnuPG project (and by extension PGP as an ecosystem) considers itself very much alive, even though practically speaking it’s effectively moribund and irrelevant.
(So I agree that it’s de facto dead, but that’s not the same thing as formal deprecation. The latter is what you do explicitly to responsibly move people away from something that’s not suitable for use anymore.)
AFAICT this is GnuPG specific and not OpenPGP related? Since GnuPG has pulled out of standards compliance anyway there are many better options. Sequoia chameleon even has drop in tooling for most workflows.
They presented critical parser flaws in all major PGP implementations, not just GNU PGP, also sequoia, minisign and age. But gpg made the worst impression to us. wontfix
From what I can piece together while the site is down, it seems like they've uncovered 14 exploitable vulnerabilities in GnuPG, of which most remain unpatched. Some of those are apparently met by refusal to patch by the maintainer. Maybe there are good reasons for this refusal, maybe someone else can chime in on that?
Is this another case of XKCD-2347? Or is there something else going on? Pretty much every Linux distro depends on PGP being pretty secure. Surely IBM & co have a couple of spare developers or spare cash to contribute?
It was a cleartext signature, not a detached signature.
Edit: even better. It was both. There is a signature type confusion attack going on here. I still didn't watch the entire thing, but it seems that unlike gpg, they do have to specify --cleartext explicitly for Sequoia, so there is no confusion going on that case.
Considering it's on cloudflare, probably just switching from their initial rebroadcast of the talk to the actual content referenced in the slides (such as https://gpg.fail/clearsig for instance)
Nope. Not yet enabled. It was submitted to HN right after the talk where they promised to make it public "really soon" after the talk. We all saw the talk live or on the stream
Okay, since there’s so much stuff to digest here and apparently there are issues designated as wontfix by GnuPG maintainers, can someone more in the loop tell us whether using gpg signatures on git commits/tags is vulnerable? And is there any better alternative going forward? Like is signing with SSH keys considered more secure now? I certainly want to get rid of gpg from my life if I can, but I also need to make sure commits/tags bearing my name actually come from me.
I did the switch this year after getting yet another personal computer. I have 4 in total (work laptop, personal sofa laptop, Mac Mini, Linux Tower). I used Yubi keys with gpg and resident ssh keys. All is fine but the configuration needed to get it too work on all the machines. I also tend to forget the finer details and have to relearn the skills of fetching the public keys into the keychain etc. I got rid of this all by moving to 1Password ssh agent and git ssh signing. Removes a lot of headaches from my ssh setup. I still have the yubi key(s) though as a 2nd factor for certain web services. And the gpg agent is still running but only as a fallback. I will turn this off next year.
Seems to be down? Here's a thread with a summary of exploits presented in the talk: https://bsky.app/profile/filippo.abyssdomain.expert/post/3ma...
Maybe the site is overloaded. But as for the "brb, were on it!!!!" - this page had the live stream of the talk when it was happening. Hopefully they'll replace it with the recording when media.ccc.de posts it, which should be within a couple hours.
> this page had the live stream of the talk when it was happening
As they said, they were on it...
Took me a second but I got your joke
it's online now
Also expect contents referred in the slides (every "chapter" of the presentation referred to a url such as https://gpg.fail/clearsig or https://gpg.fail/minisig and so on)
https://media.ccc.de/v/39c3-to-sign-or-not-to-sign-practical...
Werner Koch from GnuPG recently (2025-12-26) posted this on their blog: https://www.gnupg.org/blog/20251226-cleartext-signatures.htm...
Archive link: https://web.archive.org/web/20251227174414/https://www.gnupg...
This feels pretty unsatisfying: something that’s been “considered harmful” for three decades should be deprecated and then removed in a responsible ecosystem.
(PGP/GPG are of course hamstrung by their own decision to be a Swiss Army knife/only loosely coupled to the secure operation itself. So the even more responsible thing to do is to discard them for purposes that they can’t offer security properties for, which is the vast majority of things they get used for.)
Well python discarded signing entirely so that's one way to solve it :)
Both CPython and distributions on PyPI are more effectively signed than they were before.
(I think you already know this, but want to relitigate something that’s not meaningfully controversial in Python.)
GPG is indeed deprecated.
Most people have never heard of it and never used it.
Can you provide a source this? To my understanding, the GnuPG project (and by extension PGP as an ecosystem) considers itself very much alive, even though practically speaking it’s effectively moribund and irrelevant.
(So I agree that it’s de facto dead, but that’s not the same thing as formal deprecation. The latter is what you do explicitly to responsibly move people away from something that’s not suitable for use anymore.)
Zero-days from the CCC talk https://fahrplan.events.ccc.de/congress/2025/fahrplan/event/...
But trust in Werner Koch is gone. Wontfix??
I am curious what you mean by "trust in Werner Koch is gone". Can you elaborate?
OP is complaining about GPG team rejecting issues with "wontfix" statuses.
To be frank, at this point, GPG has been a lost cause for basically decades.
People who are serious about security use newer, better tools that replace GPG. But keep in mind, there’s no “one ring to rule them all”.
the writeup is now available and the recording lives at https://media.ccc.de/v/39c3-to-sign-or-not-to-sign-practical...
AFAICT this is GnuPG specific and not OpenPGP related? Since GnuPG has pulled out of standards compliance anyway there are many better options. Sequoia chameleon even has drop in tooling for most workflows.
They presented critical parser flaws in all major PGP implementations, not just GNU PGP, also sequoia, minisign and age. But gpg made the worst impression to us. wontfix
no, some clearsig issues are a problem in openpgp standard itself
This is depressing.
From what I can piece together while the site is down, it seems like they've uncovered 14 exploitable vulnerabilities in GnuPG, of which most remain unpatched. Some of those are apparently met by refusal to patch by the maintainer. Maybe there are good reasons for this refusal, maybe someone else can chime in on that?
Is this another case of XKCD-2347? Or is there something else going on? Pretty much every Linux distro depends on PGP being pretty secure. Surely IBM & co have a couple of spare developers or spare cash to contribute?
Haven't read it since it is down, but based on other comments, it seems to be an issue with cleartext signatures.
I haven't seen those outside of old mailing list archives. Everyone uses detached signatures nowadays, e.g. PGP/MIME for emails.
If I understood their first demo correctly, they verified a fedora iso with a detached signature. The booted iso then printed "hello 39c3". https://streaming.media.ccc.de/39c3/relive/1854
It was a cleartext signature, not a detached signature.
Edit: even better. It was both. There is a signature type confusion attack going on here. I still didn't watch the entire thing, but it seems that unlike gpg, they do have to specify --cleartext explicitly for Sequoia, so there is no confusion going on that case.
writeups are online :))
> brb, were on it!!!!
its back up!
gpg.fail fail: "brb, we're on it!"
hug of death?
Considering it's on cloudflare, probably just switching from their initial rebroadcast of the talk to the actual content referenced in the slides (such as https://gpg.fail/clearsig for instance)
Nope. Not yet enabled. It was submitted to HN right after the talk where they promised to make it public "really soon" after the talk. We all saw the talk live or on the stream