[<prev] [next>] [<thread-prev] [thread-next>] [day] [month] [year] [list]
Date: Sat, 30 Mar 2024 16:37:48 -0000 (UTC)
From: Tavis Ormandy <taviso@...il.com>
To: oss-security@...ts.openwall.com
Subject: Re: backdoor in upstream xz/liblzma leading to ssh server compromise
On 2024-03-29, Ivan Delalande wrote:
> On Fri, Mar 29, 2024 at 08:51:26AM -0700, Andres Freund wrote:
>> For which the exploit code was then adjusted:
>> https://github.com/tukaani-project/xz/commit/6e636819e8f070330d835fce46289a3ff72a7b89
>>
>> Given the activity over several weeks, the committer is either directly
>> involved or there was some quite severe compromise of their
>> system. Unfortunately the latter looks like the less likely explanation, given
>> they communicated on various lists about the "fixes" mentioned above.
>
> Knowing this, I hope the recent kernel patch series involving the same
> person to some degree will get extra scrutiny:
> https://lore.kernel.org/lkml/20240320183846.19475-1-lasse.collin@tukaani.org/t/
>
> Thanks Andres, incredible find and write-up!
>
It was also pointed out they submitted an odd PR to libarchive:
https://github.com/libarchive/libarchive/pull/1609
In summary, they replaced calls to safe_fprintf() with fprintf() --
meaning control characters are no longer filtered from errors. That
seems pretty minor, but now that we know they were in the business of
obfuscating the presence of backdoors -- seems a bit suspicious.
Regardless, that change has now been reverted:
https://github.com/libarchive/libarchive/pull/2101
Tavis.
--
_o) $ lynx lock.cmpxchg8b.com
/\\ _o) _o) $ finger taviso@....org
_\_V _( ) _( ) @taviso
Powered by blists - more mailing lists
Please check out the
Open Source Software Security Wiki, which is counterpart to this
mailing list.
Confused about mailing lists and their use?
Read about mailing lists on Wikipedia
and check out these
guidelines on proper formatting of your messages.
