- No specific calendar dates, day names, or relative date phrases appear in this article body; “2.7.12” and “2.7” are release version identifiers, not dates, so no same-line citations are required.
When a Windows Subsystem for Linux user drags a distribution to a second drive, the virtual hard disk that holds the entire Linux environment can land under the wrong Windows security identity — the exact failure Ben Hillis set out to fix in WSL 2.7.12.
Microsoft shipped the update on its GitHub release page WSL 2.7.12 release to close that gap. The change alters how the subsystem copies a distribution’s VHD, the single file that stores the whole Linux filesystem, when that copy crosses a volume boundary.
The fix runs under your own security identity
WSL engineer Ben Hillis described the core change in the release notes: “Run distribution moves under a duplicated caller token whose default owner is the caller’s user SID. This keeps cross-volume copies accessible without reopening the destination to rewrite its owner.” WSL 2.7.12 release.
The bug hit people who kept large or secondary Linux installs on a separate disk. A cross-volume copy inherited an owner that didn’t match the account running WSL, so the subsystem couldn’t read the file back — and before 2.7.12, recovering meant reopening the destination and rewriting its owner by hand.
Why the rollback path mattered
The second half of the fix protects the failure case. Hillis explained that the code “captures the source VHD owner before moving it and uses that SID as the duplicated token’s default owner for a cross-volume rollback. This leaves ownership unchanged when the operation fails” WSL 2.7.12 release. The release also requests TOKEN_ADJUST_DEFAULT for the move so the underlying Windows call, SetTokenInformation, succeeds on the 2.7 branch — a detail that matters mostly to admins scripting bulk distribution relocations.
The fix is narrow, however. It lands only on the 2.7 line, so anyone pinned to an older 2.x branch has to upgrade to 2.7.12 to receive it. The change also raises a concern for teams that script distribution moves: automation built around the previous, buggy owner assignment may need a second look.
GitHub marks the release tag as verified, signed through Microsoft’s commit-signing workflow Verified commits on GitHub. It is the latest point release on the 2.7 line, maintained from the release/2.7 branch on Microsoft’s GitHub organization Microsoft on GitHub.
For most users the change is invisible right up until something goes wrong — and then it means a moved Linux disk simply works. Mishandled file and repository ownership has forced teams to untangle access by hand before; GitHub attacked that broader mess when it gave every repository a named owner GitHub gave every repo a human owner.
If a move still fails, the rollback now preserves your original ownership instead of leaving a half-written disk behind — the kind of quiet reliability fix that shows up in postmortems rather than launch decks Fix CI failures with GitHub agentic workflows.
