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GnuPG, Infosec (-) 

"SKS Keyserver Network Under Attack"
gist.github.com/rjhansen/67ab9

TL;DR: The SKS keyservers are designed to be append-only, and they are being abused with large amounts of signatures on some keys. GnuPG has trouble dealing with that many signatures, and the mere action of importing or refreshing the trust DB with one of these keys breaks your installation, and it becomes a mess to use and fix. The workaround in the short/medium term is to stop using SKS keyservers altogether.

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GnuPG, Infosec (-) 

This becomes extra problematic because many people use GnuPG without noticing: it is behind the core piece verifying the integrity in many package managers in Linux distros. Some developers automatically sign their commits with GnuPG as well.
And this attack is now unprecedented; it has been shown to be an issue before, but now the scope of the attack is far larger than it has ever been.

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GnuPG, Infosec (-) 

@shello I am not sure that is a short/medium term workaround.

The SKS keyserver pool has been problematic for a long time, this may just be the final nail in the coffin.

Better things exist now; WKD and keys.openpgp.org in particular. And Autocrypt for folks who like TOFU.

GnuPG, Infosec (-) 

@HerraBRE Fair, I worded that toot kind of poorly. But GnuPG should also receive some sort of mitigation (apparently there's been discussion about that for the past year or so).
I agree this might just be the end of the road for SKS. Some design choices aged poorly, and it doesn't seem to fit the understanding we have for threats in 2019.

GnuPG, Infosec (-) 

@shello Oh yeah, GnuPG needs to learn not to crap its pants.

... but I'm also willing to grant Werner that this may be very hard to deal with in the general case.

The PGP packet format is very expressive and complex, and packets relate to each-other in confusing, computationally intensive ways. I'm guessing that any complete implementation will be easily DOS-able if you can feed it arbitrary data.

Letting randos put stuff on your key has always been a terrible idea.

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