And the stock plugin ships an unaligned atomic that triggers the kernel's split_lock detector on every modern Intel CPU. Startup stalls for 25-60 seconds while the kernel walks each trap; every Device-tab click hits it again. The workaround (sysctl kernel.split_lock_mitigate=0) degrades system-wide performance and still misbehaves in LAN-only mode. Reported to Bambu over a year ago and still open: bambulab/BambuStudio#8605.

And no ARM or non-x86_64 build

* 2022-05-29: Admitted it's based on PrusaSlicer [https://blog.bambulab.com/to-open-or-not-to-open-that-is-the...](https://blog.bambulab.com/to-open-or-not-to-open-that-is-the...) * "We would like to ask for the understanding of the community to give us some time *before we open-source* Parts 1 and 2, which is scheduled for the second half of this year." - admitted it's currently an AGPL violation

* 2022-06-29: Evidence. "GPL requires release of source the moment binaries are out. Many people have had the binaries for weeks. They are 100% in violation". [https://x.com/DreadMakerAdam/status/1542216014984876036](https://x.com/DreadMakerAdam/status/1542216014984876036)

* ???

* 2022-07-15: They only dumped it (with prior git history squashed) onto GitHub months after the initial release, after immense community pressure. [https://www.reddit.com/r/OpenBambu/comments/1thfslw/comment/...](https://www.reddit.com/r/OpenBambu/comments/1thfslw/comment/...) [https://github.com/bambulab/BambuStudio/issues/1](https://github.com/bambulab/BambuStudio/issues/1)

That's why any sane software uses a stable public API and an internal one that can be closed off or has breaking changes all the time.

> MQTT has no versioning and limited hierarchy in the pub / sub model

It's currently handled like this: https://github.com/Doridian/OpenBambuAPI/blob/main/mqtt.md. Would it be a far stretch to add an "api_version":x field and a "internal_" prefix for some commands?

The problem is hackers don't need to play by the rules (accessing the display).

8 digits that never change is a joke in terms of security, it could be brute-forced within hours/days by sending a network request for each possible combination.

mitm: afaik Bambu Studio/Connect/Handy validate the printer's certificate during the TLS handshake, but most third party software probably doesn't (barely found documentation about it).

And there are a few other (although not as fundamental) weaknesses like no mutual authentication, access control or revocation of specific clients. Due to the nature of MQTT, every client can see messages sent by other clients once authenticated.

The issue is introducing further measures which don't provide any security benefit to the user (can be spoofed): only allowing critical commands from BambuConnect.

Already works that way and isn't affected by this update: https://wiki.bambulab.com/en/security-incidents-cloud-traffi..., https://github.com/Doridian/OpenBambuAPI/blob/main/mqtt.md#l...

- what the firmware does: verify these operations, meaning it can reject MQTT messages with an invalid/missing signature from third party software

- the big flaw with that approach: by extracting the key, third party software can get full access again

- improvement to security: none (that obfuscation layer doesn't prevent anything if the printer/cloud were vulnerable)

authentication stays the same as before: https://git.devminer.xyz/archive/bambu-connect/src/commit/47...