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Re:Backdoor in upstream xz/liblzma leading to SSH server com... by junon on Friday March 29, 2024 @07:16PM (#39870098)
GitHub has suspended @JiaT75's account.

EDIT: Lasse Collin's account @Larhzu has also been suspended.

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EDIT: Just did a bit of poking. xz-embedded was touched by Jia as well and it appears to be used in the linux kernel. I did quick look and it doesn't appear Jia touched anything of interest in there. I also checked the previous mirror at the tukaani project website, and nothing was out of place other than lagging a few commits behind:

https://gist.github.com/Qix-/f1a1b9a933e8847f56103bc14783ab7...

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Here's a mailing list message from them ca. 2022.

https://listor.tp-sv.se/pipermail/tp-sv_listor.tp-sv.se/2022...

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MinGW w64 on AUR was last published by Jia on Feb 29: https://aur.archlinux.org/cgit/aur.git/log/?h=mingw-w64-xz (found by searching their public key: 22D465F2B4C173803B20C6DE59FCF207FEA7F445)

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pacman-static on AUR still lists their public key as a contributor, xz was last updated to 5.4.5 on 17-11-2023: https://aur.archlinux.org/cgit/aur.git/?h=pacman-static

EDIT: Actually the sources list 5.6.1, which is pulling the XZ specifically (not the auto-generated GZ): https://aur.archlinux.org/packages/pacman-static

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Alpine was patched as of 6 hours ago.

https://git.alpinelinux.org/aports/commit/?id=982d2c6bcbbb57...

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OpenSUSE is still listing Jia's public key: https://sources.suse.com/SUSE:SLE-15-SP6:GA/xz/576e550c49a36... (cross-ref with https://web.archive.org/web/20240329235153/https://tukaani.o...)

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Arch appears to still list Jia as an approved publisher, if I'm understanding this page correctly.

https://gitlab.archlinux.org/archlinux/packaging/packages/xz...

EDIT: Just sent an email to the last committer to bring it to their attention.

EDIT: It's been removed.

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jiatan's Libera info indicates they registered on Dec 12 13:43:12 2022 with no timezone information.

    -NickServ- Information on jiatan (account jiatan):
    -NickServ- Registered : Dec 12 13:43:12 2022 +0000 (1y 15w 3d ago)
    -NickServ- Last seen : (less than two weeks ago)
    -NickServ- User seen : (less than two weeks ago)
    -NickServ- Flags : HideMail, Private
    -NickServ- jiatan has enabled nick protection
    -NickServ- *** End of Info ***
They are not registered on freenode.
Re:Backdoor in upstream xz/liblzma leading to SSH server com... by junon on Friday March 29, 2024 @10:17PM (#39871231)
Just for posterity since I can no longer edit: Libera staff has been firm and unrelenting in their position not to disclose anything whatsoever about the account. I obtained the last point on my own. Libera has made it clear they will not budge on this topic, which I applaud and respect. They were not involved whatsoever in ascertaining a VPN was used, and since that fact makes anything else about the connection information moot, there's nothing else to say about it.
Re:Backdoor in upstream xz/liblzma leading to SSH server com... by Fnoord on Saturday March 30, 2024 @11:55AM (#39876042)
You applaud and respect this?

Either way, I do hope LE will get into this. They better cooperate.

Re:Backdoor in upstream xz/liblzma leading to SSH server com... by freeone3000 on Saturday March 30, 2024 @12:10PM (#39876161)
Respect not giving out identifying information on individuals whenever someone asks, no matter what company they work for and what job they do? Yes. I respect this.
Re:Backdoor in upstream xz/liblzma leading to SSH server com... by junon on Saturday March 30, 2024 @12:19PM (#39876224)
I am not LE nor a government official. I did not present a warrant of any kind. I asked in a channel about it. Libera refused to provide information. Libera respecting the privacy of users is of course something I applaud and respect. Why wouldn't I?
Re:Backdoor in upstream xz/liblzma leading to SSH server com... by supposemaybe on Saturday March 30, 2024 @01:11PM (#39876618)
I hope you aren’t in control of any customer data.
Re:Backdoor in upstream xz/liblzma leading to SSH server com... by flykespice on Saturday March 30, 2024 @05:32PM (#39878877)
It's called keeping integrity on not disclosing private info any users from your network, regardless whether they are bad actors.

I respect them for that.

Violating that code is just as bad as the bad actor slipping backdoors.

Re:Backdoor in upstream xz/liblzma leading to SSH server com... by Phenylacetyl on Saturday March 30, 2024 @03:37AM (#39872693)
The alpine patch includes gettext-dev which is likely also exploited as the same authors have been pushing gettext to projects where their changes have been questioned
Re:Backdoor in upstream xz/liblzma leading to SSH server com... by jwilk on Saturday March 30, 2024 @07:28AM (#39873830)
What do you mean?
Re:Backdoor in upstream xz/liblzma leading to SSH server com... by everybackdoor on Saturday March 30, 2024 @09:32AM (#39874698)
Look at the newest commits, do you see anything suspicious:

https://git.alpinelinux.org/aports/log/main/gettext

libunistring could also be affected as that has also been pushed there

Re:Backdoor in upstream xz/liblzma leading to SSH server com... by jwilk on Saturday March 30, 2024 @12:08PM (#39876145)
> do you see anything suspicious

No.

> libunistring could also be affected as that has also been pushed there

What do you mean by "that"?

Re:Backdoor in upstream xz/liblzma leading to SSH server com... by whoopdedo on Saturday March 30, 2024 @10:41AM (#39875338)
Seeing so many commits that are "skip failing test" is a very strong code smell.
Re:Backdoor in upstream xz/liblzma leading to SSH server com... by gray_-_wolf on Monday April 01, 2024 @07:40AM (#39893056)
Yes, but it is often a sad reality of trying to run projects mainly written for glibc on musl. Not many people write portable C these days.
Re:Backdoor in upstream xz/liblzma leading to SSH server com... by account42 on Tuesday April 02, 2024 @07:40AM (#39904581)
It's still the wrong way to go about things. Tests are there for a reason, meaning if they fail you should try to understand them to the point where you can fix the problem (broken test or actual bug) instead of just wantonly distabling tests until you get a green light.
Re:Backdoor in upstream xz/liblzma leading to SSH server com... by mook on Saturday March 30, 2024 @04:50AM (#39873022)
FWIW, that's mingw-w64-xz (cross-compiled xz utils) in AUR, not ming-w64 (which would normally refer to the compiler toolchain itself).
Re:Backdoor in upstream xz/liblzma leading to SSH server com... by junon on Saturday March 30, 2024 @06:05AM (#39873395)
Good catch, thanks :)
Re:Backdoor in upstream xz/liblzma leading to SSH server com... by reisse on Saturday March 30, 2024 @07:47AM (#39873943)
> EDIT: Github has disabled all Tukaani repositories, including downloads from the releases page.

Why? Isn't it better to freeze them and let as many people as possible analyze the code?

Re:Backdoor in upstream xz/liblzma leading to SSH server com... by junon on Saturday March 30, 2024 @08:22AM (#39874159)
Good question, though I can imagine they took this action for two reasons:

1. They don't have the ability to freeze repos (i.e. would require some engineering effort to implement it), as I've never seen them do that before.

2. Many distros (and I assume many enterprises) were still linking to the GitHub releases to source the infected tarballs for building. Disabling the repo prevents that.

The infected tarballs and repo are still available elsewhere for researchers to find, too.

Re:Backdoor in upstream xz/liblzma leading to SSH server com... by nihilanth on Saturday March 30, 2024 @08:54AM (#39874389)
They could always archive it. Theoretically (and I mean theoretically only), there's another reason for Microsoft to prevent access to repo: if a nation state was involved, and there've been backdoor conversations to obfuscate the trail.
Re:Backdoor in upstream xz/liblzma leading to SSH server com... by jarfil on Saturday March 30, 2024 @03:11PM (#39877690)
Archiving the repo doesn't stop the downloads. They would need to rename it in order to prevent distro CI/CD from keeping downloading untrustworthy stuff.
Re:Backdoor in upstream xz/liblzma leading to SSH server com... by account42 on Tuesday April 02, 2024 @07:26AM (#39904508)
Distros downloading directly from GitHub deserve what they get.
Re:Backdoor in upstream xz/liblzma leading to SSH server com... by Sebb767 on Saturday March 30, 2024 @08:21AM (#39874150)
You can still find the source everywhere, if you look for it. Having a fine-looking page distribute vulnerable source code is a much bigger threat.
Re:Backdoor in upstream xz/liblzma leading to SSH server com... by AtNightWeCode on Saturday March 30, 2024 @09:18AM (#39874587)
Maybe one can get the code from here. New commits being added it seems.

https://git.tukaani.org/

Re:Backdoor in upstream xz/liblzma leading to SSH server com... by ptx on Saturday March 30, 2024 @12:04PM (#39876115)
The latest commit is interesting (f9cf4c05edd14, "Fix sabotaged Landlock sandbox check").

It looks like one of Jia Tan's commits (328c52da8a2) added a stray "." character to a piece of C code that was part of a check for sandboxing support, which I guess would cause the code to fail to compile, causing the check to fail, causing the sandboxing to be disabled.

Re:Backdoor in upstream xz/liblzma leading to SSH server com... by junon on Saturday March 30, 2024 @12:53PM (#39876466)
Lasse has also started his own documentation on the incident.

https://tukaani.org/xz-backdoor/

Re:Backdoor in upstream xz/liblzma leading to SSH server com... by josefx on Saturday March 30, 2024 @04:28PM (#39878307)
Shouldn't they have tests running to ensure that the check works on at least some systems?
Re:Backdoor in upstream xz/liblzma leading to SSH server com... by windenntw on Sunday March 31, 2024 @06:30AM (#39883011)
What do you mean "tests"?
Re:Backdoor in upstream xz/liblzma leading to SSH server com... by josefx on Monday April 01, 2024 @09:25AM (#39893948)
Have a system were you wxpect the sandboxing to work and have an automated check that it compiles there?
Re:Backdoor in upstream xz/liblzma leading to SSH server com... by ptx on Tuesday April 02, 2024 @07:42AM (#39904607)
Part of the backdoor was in the tests. The attacker in this case could easily have sabotaged the test as well if a test was required.
Re:Backdoor in upstream xz/liblzma leading to SSH server com... by account42 on Tuesday April 02, 2024 @07:34AM (#39904555)
If your project becomes complex enough eventually you need tests for the configure step. Even without malicious actors its easy to miss that a compiler or system change broke some check.
Re:Backdoor in upstream xz/liblzma leading to SSH server com... by megous on Saturday March 30, 2024 @11:11AM (#39875583)
Yeah, another of the reasons not to host anything on Github but optional git mirrors, if you don't want your FOSS project to be subject to Microsoft playing a "world police".
Re:Backdoor in upstream xz/liblzma leading to SSH server com... by junon on Saturday March 30, 2024 @12:23PM (#39876261)
Don't agree here. I've only ever seen GitHub do this in extreme circumstances where they were absolutely warranted.
Re:Backdoor in upstream xz/liblzma leading to SSH server com... by megous on Saturday March 30, 2024 @02:33PM (#39877394)
You mean like when they banned all people from wirte access who didn't want to jump to their 2FA bandwagon?
Re:Backdoor in upstream xz/liblzma leading to SSH server com... by godelski on Saturday March 30, 2024 @11:40AM (#39875889)
You can find it on archive. Someone archived it last night
Re:Backdoor in upstream xz/liblzma leading to SSH server com... by hypnagogic on Saturday March 30, 2024 @01:26PM (#39876757)
Asking this here too: why isn't there an automated A/B or diff match for the tarball contents to match the repo, auto-flag with a warning if that happens? Am I missing something here?
Re:Backdoor in upstream xz/liblzma leading to SSH server com... by nolist_policy on Saturday March 30, 2024 @02:20PM (#39877275)
The tarballs mismatching from the git tree is a feature, not a bug. Projects that use submodules may want to include these and projects using autoconf may want to generate and include the configure script.
Re:Backdoor in upstream xz/liblzma leading to SSH server com... by ano-ther on Saturday March 30, 2024 @02:35PM (#39877418)
Re:Backdoor in upstream xz/liblzma leading to SSH server com... by hypnagogic on Sunday March 31, 2024 @10:02AM (#39884351)
"lol"

> Those days are pretty much behind us. Sure, you can compile code and tweak software configurations if you want to--but most of the time, users don't want to. Organizations generally don't want to, they want to rely on certified products that they can vet for their environment and get support for. This is why enterprise open source exists. Users and organizations count on vendors to turn upstreams into coherent downstream products that meet their needs.

> In turn, vendors like Red Hat learn from customer requests and feedback about what features they need and want. That, then, benefits the upstream project in the form of new features and bugfixes, etc., and ultimately finds its way into products and the cycle continues.

"and when the upstream is tainted, everyone drinks poisoned water downstream, simple as that!"

Re:Backdoor in upstream xz/liblzma leading to SSH server com... by hypnagogic on Sunday March 31, 2024 @09:54AM (#39884271)
> The tarballs mismatching from the git tree is a feature, not a bug.

A feature which allowed the exploit to take place, let's put it that way.

Over here: https://gist.github.com/thesamesam/223949d5a074ebc3dce9ee78b...

> The release tarballs upstream publishes don't have the same code that GitHub has. This is common in C projects so that downstream consumers don't need to remember how to run autotools and autoconf. The version of build-to-host.m4 in the release tarballs differs wildly from the upstream on GitHub.

Multiple suggestions on that thread on how that's a legacy practice that might be outdated, especially in the current climate of cyber threats.

Someone even posted a more thorough gist on what could be done to increase transparency and reduce discrepancies between tarballs and repos: https://gist.github.com/smintrh78/97b5cb4d8332ea4808f25b47c8...

Re:Backdoor in upstream xz/liblzma leading to SSH server com... by mikolajw on Saturday March 30, 2024 @01:45PM (#39876938)
I've posted an earlier WHOWAS of jiatan here: https://news.ycombinator.com/item?id=39868773
Re:Backdoor in upstream xz/liblzma leading to SSH server com... by junon on Saturday March 30, 2024 @02:25PM (#39877321)
It appears to be an RCE, not a public key bypass: https://news.ycombinator.com/item?id=39877312
Re:Backdoor in upstream xz/liblzma leading to SSH server com... by menomatter on Tuesday April 02, 2024 @03:32PM (#39909926)
account is back online https://github.com/JiaT75
Re:Backdoor in upstream xz/liblzma leading to SSH server com... by account42 on Wednesday April 03, 2024 @03:47AM (#39914643)
Hopefully still locked just visible so people can find and alayze his contributions.