[Here (I think) is the very minimal new Launchpad bug report for this issue](https://bugs.launchpad.net/ubuntu/+source/appstream/+bug/1709144).

IMHO, because it has upvotes and upvoted answers, **https://askubuntu.com/questions/943463/library-corruption-error-during-apt-get-update** is looking like the master post - https://askubuntu.com/questions/943832/after-automatic-upgrade-apt-get-update-cause-error-in-appstreamcli-double-f is already closed against it.

However, I think the answers need expansion - at least someone should add to the answers or post a new answer with a link to the bug report and advise people affected to add themselves to affected users on the bug report. The current workaround is apparently to remove the package. What are the consequences of doing so? Presumably people will want to reinstall it when a fix is released. No answer anywhere covers this properly, it seems to me.

This post is quite old: https://askubuntu.com/questions/894519/ubuntu-16-04-enable-wifi-giving-error-while-get-update. [The fix][1] posted there by Yaron is from May 2016, and suggests installing version **`0.9.4-1`** which I think was the "fixed" upstream version at the time, but the current, broken package is seemingly **`0.10.6-2`** so this is a substantial downgrade and may not be the best idea. A new user who posted the same link as [an answer](https://askubuntu.com/a/943018/527764) to https://askubuntu.com/questions/942895/e-problem-executing-scripts-aptupdatepost-invoke-success said it "worked for me" although *when* is unclear and the long-term consequences of downgrading are to be discovered... Nonetheless, merging the latter post with the master may be beneficial if we can improve the answers to inform users fully about what they are doing.

For now I have voted to close https://askubuntu.com/questions/943840/cannot-update-software and https://askubuntu.com/questions/837512/segmentation-fault-while-updating-repositories (although it is an old post and probably relates to [an older, fixed bug](https://bugs.launchpad.net/ubuntu/+source/appstream/+bug/1579712) and on second thoughts should probably be closed as no-repro) and https://askubuntu.com/questions/943463/library-corruption-error-during-apt-get-update and https://askubuntu.com/questions/942895/e-problem-executing-scripts-aptupdatepost-invoke-success against https://askubuntu.com/questions/943463/library-corruption-error-during-apt-get-update.

I hope someone with better knowledge will be able to improve the master post. I will check back later and if no one has I will try to do some further research and fix it myself, but I am sure others could do a better job.

[1]: https://bugs.launchpad.net/ubuntu/+source/appstream/+bug/1579712/comments/24