Bambu Lab explained in its forum on November 12, 2026, why Bambu Cloud had to block conspicuous requests this week. The number of requests rose to about 34 times the normal level within an hour and peaked at roughly 20 million requests per day. Some users were also affected by the block; according to Bambu Lab, the service is now running stably again.
Almost all of the conspicuous requests retrieved the status of print jobs and came from many private IP addresses. They carried the identifier (the user agent) of OrcaSlicer along with an older network plug-in, so Bambu Lab initially attributed them to OrcaSlicer users.
The OrcaSlicer team pointed Bambu Lab to other integrations, including ha-bambulab for Home Assistant. According to the release notes, the maintainers of ha-bambulab have fixed the bug and released version 2.4.0 on November 11, 2026. However, Bambu Lab has not confirmed that all of the traffic originated from there.
What is third-party software allowed to do in Bambu Cloud?
According to Bambu Lab, third-party software may continue to use non-critical cloud functions, such as status messages with temperature, position, speed, and print progress. These queries remain available as long as they stay moderate. If there is a risk of overload, Bambu Lab can limit requests or temporarily suspend access.
What third-party software may do in the cloud
How Bambu Lab separates display and control, as of November 12, 2026
Intended
- Retrieve print status
- Display temperature and position
- Display speed and progress
Not intended
- Connect printer to the account
- Watch live video
- Start a print
- Update firmware
For print jobs, Bambu Lab names Bambu Connect as the supported route
Source: Bambu Lab Forum
The situation is different for commands that change a printer's behavior or involve security-relevant access. These include connecting a printer to the account, live video, starting a print, and firmware updates. For these commands, Bambu Lab does not provide for direct access by third-party software and names Bambu Connect as the supported route for print jobs.
Bambu Lab describes the same separation in the wiki on third-party integration: status messages for tools such as Home Assistant remain possible without authorization, while commands such as starting a print require authorization. Bambu Lab does not announce a new rule in the forum, but it does announce throttling and blocking in case of overload.
What changes for Home Assistant and OrcaSlicer?
According to the release notes, version 2.4.0 of ha-bambulab fixes a bug that repeatedly triggered the same requests to Bambu services until Bambu Lab blocked the integration via Cloudflare. In addition, the integration now identifies itself with its own identifier, so that Bambu Lab can recognize it more easily in the future.
For OrcaSlicer itself, Bambu Lab names no measure. However, a block based on the identifier also affects users who have nothing to do with it but send the same identifier. Bambu Lab therefore asks developers to have their software appear under its own name.
What this means for you
It's best to update ha-bambulab in Home Assistant to version 2.4.0 or newer, especially if printer status or notifications failed this week. Whether your outages were caused by the block cannot be verified, as Bambu Lab names neither an exact time period nor affected accounts.
For your own scripts that access Bambu Cloud, the following applies: it's best to set your own identifier instead of the one from OrcaSlicer and to query the print status only sparingly.
As a way to become more independent of the cloud, the wiki names Developer Mode in LAN mode. According to the wiki, in this mode third-party software continues to work without authorization, but the printer then no longer connects to the cloud. It's best to check in the wiki whether your model and firmware support it.
Bambu Lab published the postmortem on November 12, 2026; ha-bambulab 2.4.0 was released on November 11, 2026.
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