Microsoft is to release only four security updates in its July Patch Tuesday security update, but these will cover 22 vulnerabilities in Windows and Office.
The highest priority update is rated "critical" and affects only Windows 7 and Windows Vista.
Amol Sarwate, vulnerability labs manager for Qualys, said the second highest priority will most likely be bulletin four, which fixes a remote code execution in Visio 2003 SP3.
The other two updates are rated "important" and affect Windows 7, Vista, XP and 2008.
Many companies will have limited exposure for the software affected, said Sarwate.
Although this is a relatively small release compared with June's 16 bulletins and is consistent with the cycle of smaller patches every other month, Microsoft says three of the four updates will require system restarts.