I found this! I posted a semi-click-bait-ey tweet about it here [0], I think it’s important for people know how easy these bugs are to find now. It’s becoming borderline irresponsible not to audit your internet-facing code with modern AI tools.
Nice work! A similar vulnerability in 2019 also found by you included the recommendation to update with:
apt -o Acquire::http::AllowRedirect=false update
apt -o Acquire::http::AllowRedirect=false upgrade
Speaking of which… if any of y’all work on security at OpenAI I have some questions for you about Daybreak! Please email me
But how do I update apt if apt is untrustable until fixed ? Good ol' .deb scp'd in dpkg'd.
dupe (2h ago): https://news.ycombinator.com/item?id=50364814
I feel like they should release manual update instructions since the update mechanism is vulnerable. Although I see my systems already updated via unattended upgrades.
edit: On lobste.rs I see a recommendation for `apt download`: https://lobste.rs/s/h7bvma/man_middle_arbitrary_code_executi...
How would an attacker inject a redirect into an apt package download?
MITM on the network, I guess like DNS takeover or the like.
So you pass through the upstream headers but then simulate a failure/resume and supply different contents for the resumed download.
So apt doesn't verify signatures on what is actually downloaded?
> Improper file handling when resuming an HTTP download allows a man-in-the-middle attacker to replace a package after verification
from the OP
APT can use HTTPS, but often doesn't, making a MITM attack easier (also the idea for a long time has been signatures are enough, and/or TLS certs used to be a lot harder to get, but at this point you should really be using both).
Https doesn't help with this if the MitM is the apt mirror you are using.
One reason http is still used is because you need an independent signature anyway since it is common to use mirrors that don't have the same level of trust as the debian maintainers
Still doesn't make sense to me. So package A is downloaded, signature verified, then package B is downloaded, but somehow the package A file is replaced? Is it something like that?
Discussion here: https://news.ycombinator.com/item?id=50364814