Acrobat Protected Mode Becomes Mandatory in 2026
Adobe is retiring the option to switch off the Adobe Acrobat sandbox — macOS in October 2026, Windows in December 2026. Our Windows plug-ins are being updated ahead of it.
Adobe has announced that the option to switch off its security sandbox is going away. In an announcement on the Adobe community forums, Adobe confirmed that Sandbox on macOS and Protected Mode on Windows will become mandatory, with no way to turn them off.
For most people opening a PDF, nothing will change. For anyone running third-party plug-ins inside Adobe Acrobat — including ours — it is a deadline worth knowing about.
What is changing, and when
Adobe is retiring the temporary option that let users and administrators disable the sandbox. The dates are staggered by platform:
- macOS — October 2026. Sandbox becomes mandatory.
- Windows — December 2026. Protected Mode becomes mandatory.
After those dates, Acrobat, Acrobat Reader and every third-party plug-in must operate inside the sandbox. Adobe has been explicit that this is one-way: once the option is removed on your platform, there is no supported way to disable the sandbox again.
What Protected Mode actually does
Protected Mode runs Acrobat's document-rendering work in a separate process with deliberately reduced privileges. That process cannot freely read and write arbitrary files, reach into the registry, or call out to the wider system. If a malformed PDF manages to exploit a rendering bug, the attacker lands in a process that can do very little, rather than one running with the user's full rights.
It is a well-established defence, and Adobe's position is straightforward: the strongest available protection should be on for everyone, not only for those who leave the default alone.
Why this matters for plug-ins
A plug-in is loaded into that same restricted process, so it inherits the same restrictions. Operations a plug-in might once have performed directly — writing an exported file to disk, reading a configuration file, touching the registry, launching a helper application — are exactly the operations the sandbox is designed to prevent.
This is the root of a problem some customers will recognise. A plug-in written before sandboxing that tries to write a file directly will not always produce a clear permissions error; it may simply appear not to work. Historically the workaround was to switch Protected Mode off. From December 2026 on Windows, that workaround stops existing.
How a plug-in works inside the sandbox
Adobe's answer is the sandbox broker extensibility mechanism in the Acrobat SDK. The privileged work moves out of the sandboxed process and into a separate broker process that still runs with full rights. The plug-in asks; the broker decides and acts.
In practice a sandbox-ready plug-in is built in two halves that talk to each other:
- The plug-in itself, loaded into the restricted process, which can no longer perform privileged operations directly.
- A plug-in broker, which extends the broker APIs at runtime through the
SandboxHFThost function table that Adobe publishes for exactly this purpose. - A handshake between the two at start-up, after which the plug-in delegates privileged work through CrossCalls rather than attempting it itself.
Adobe ships simple-ipc-lib and the SandboxPISDK to support this work. It is not a recompile: it means splitting a plug-in into client and server components, deciding which operations genuinely need elevated rights, and implementing each of those as a call the broker can validate and carry out. That is the work Adobe is asking developers to complete before the deadlines.
Where Mapsoft stands
All Mapsoft Acrobat plug-ins for Windows are being updated to run with Protected Mode switched on, and those updates are coming soon — well ahead of the December 2026 deadline. When each one is released you will not need to disable Protected Mode to use it.
The upgrade path will be the usual one: download the installer for your product and install it over the existing version. Customers with a valid licence will get the update at no additional cost. We will announce the releases here and on the product pages as they land.
If you were told to switch Protected Mode off. Some of our older installation notes advised unchecking Protected Mode when a plug-in could not reach external files or the registry. That advice still applies to the builds shipping today, and it will keep working until Adobe removes the option. Plan on the Protected Mode updates instead: after December 2026 the setting will not be there to switch off.
What to do before the deadlines
- Watch for the Protected Mode releases on the products page, and update as each plug-in you use is published.
- Stop relying on the opt-out. If a deployment script, group policy or build image disables Protected Mode, plan its removal now rather than in December 2026.
- Check your other plug-ins. Anything third-party in your Acrobat installation faces the same deadline; ask each vendor where they stand.
- Test with Protected Mode on, so you find any workflow that depended on it being off while there is still time to change it.
If you are unsure whether a particular Mapsoft product or version is ready, our support page has compatibility information and the team is happy to advise directly. If you maintain your own Acrobat plug-in and want help with the broker work, that is precisely the kind of project our Adobe development team takes on.
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Questions About Protected Mode?
If you are unsure whether your plug-ins are ready for the 2026 deadlines, get in touch with our team.