MICROSOFT’S September 2026 Patch Tuesday included a security update for Excel, designated KB5002914, which is intended to fix remote code execution and information disclosure vulnerabilities but instead causes a disruptive defect in copying, pasting and formula dragging.
The update released on 9 September 2026 appears to affect Excel across multiple versions—claims from users indicate that not only Excel 2016 but also Excel 2019, 2021 and 2024 may be affected, even though Microsoft’ s notes primarily reference Excel 2016. The reported symptom is precise: when a paste is performed, the source cell remains selected while the destination cell fills with nothing; there is no error prompt and no audible alert.
At the time of reporting, Microsoft had confirmed only the break in copy-paste functionality, while the related formula-dragging issue remained unconfirmed on official channels.
Beyond copying and pasting, community feedback suggests additional misbehaviour such as dragging formulas to recalculate or moving cells after installing the update, with some users experiencing the Excel process crashing and restarting so quickly that the operation appears simply unresponsive. As a temporary measure, the article notes that there is no official workaround from Microsoft, and recommends uninstalling the update to restore normal Excel operation after a restart.
However, given that security updates typically pack numerous vulnerability fixes, IT admins are advised to weigh security implications before rolling back the patch. The source page links to the official KB5002914 support page for ongoing updates.