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This isn't directly perl-related, but it's a good reminder that as the bus-factor of our projects dwindle down to 0, the danger of a dependency attack goes up.

Obligatory XKCD

The story is still unfolding, and I've just been reading it from the HN post

In this case, it appears that the maintainer of xz-utils, who has been maintaining it since 2009 and mentioned online that they don't really have the capacity for it anymore finally had a motivated helper show up to assist with the work 2.5 years ago. That motivated helper now appears to either be a long-con state actor, or a compromised account.

liblzma is used by libsystemd. Redhat and Debian patch ssh to use libsystemd. The startup code of libxz detects when it is loaded into sshd during initialization and replaces a core auth function of sshd with its own copy. The malicious code comes from compressed compiled code within one of the libxz unit test files that gets sneakily injected into the build during the ./configure script. The person who discovered it only found it due to valgrind errors and a slower startup time for ssh, which are mistakes a more sophisticated attacker might not have made.

Oh, and of course the question on everyone's mind, you're probably not affected yet because the latest liblzma is only used in pre-release distros right now. But check if you have xz 5.6 or later. However, the author has been contributing to xz for 2.5 years so who knows if this is the first attack or not...

submitted by /u/nrdvana
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