The PDF ("sec23summer...") has metadata creation/modification timestamp of 20221004165319Z (October 2022). So presumably the paper was written last October and released for Usenix 2023.

(Reference [12] is from Usenix July 2022. See "Prior work" in the introduction).

October 4th 2022, according to the PDF date (and according to the "We have not received any feedback from OnlyOffice as of October 4th, 2022" in the PDF).

One of the authors lists the paper as 2023 on their homepage [1], and the naming of a preprint [2] suggests summer 2023.

It's a recent paper.

[1] https://casa.rub.de/en/research/publications/detail/every-si...

[2] https://www.usenix.org/system/files/sec23summer_235-rohlmann...

USENIX '23 will take place in August.

It's listed as a summer deadline accepted paper for USENIX Security 2023: https://www.usenix.org/conference/usenixsecurity23/summer-ac...

Per the call for papers [https://www.usenix.org/conference/usenixsecurity23/call-for-...], that means the paper would have been submitted for review by June 7, 2022, accepted for publication as of September 2, 2022, and had the final ("camera-ready") version uploaded by October 4, 2022.

The conference itself won't take place until August of this year.