VeraCrypt: Missing authorization on veracrypt.sys IOCTLs exposes disk topology, symlink targets, and DeviceObject reference count to any client of \\.\VeraCrypt

VeraCrypt provides disk encryption with strong security based on TrueCrypt. In 1.26.29 and earlier, selected metadata IOCTL handlers in the VeraCrypt Windows veracrypt.sys driver accept caller-supplied object-manager and device paths broader than supported VeraCrypt workflows require. A local user who can open the intentionally user-accessible \.\VeraCrypt device can use TC_IOCTL_GET_RESOLVED_SYMLINK, TC_IOCTL_GET_DRIVE_PARTITION_INFO, VC_IOCTL_GET_DRIVE_GEOMETRY_EX, or the legacy TC_IOCTL_GET_DRIVE_GEOMETRY handler to make src/Driver/Ntdriver.c perform kernel-context symbolic-link or disk-device lookups outside the intended path scope. This can disclose low-sensitivity drive-letter targets, partition information, disk geometry, GPT or MBR state, and limited object-manager path metadata.