Errata patches for net80211 have been released for OpenBSD 6.8 and 6.9. Insufficient validation of A-MSDUs and fragmented 802.11 frames could be abused to inject arbitrary frames.
Binary updates for the amd64, i386, and arm64 platforms are available via the syspatch utility. Source code patches can be found on the respective errata page: https://www.openbsd.org/errata68.html https://www.openbsd.org/errata69.html As these affect the kernel, a reboot will be needed after patching.