High severity8.4NVD Advisory· Published May 12, 2026· Updated Jun 1, 2026
CVE-2026-40358
CVE-2026-40358
Description
Heap-based buffer overflow in Microsoft Office allows an unauthorized attacker to execute code locally.
Affected products
13cpe:2.3:a:microsoft:office_long_term_servicing_channel:2021:*:*:*:*:macos:*:*+ 5 more
- cpe:2.3:a:microsoft:office_long_term_servicing_channel:2021:*:*:*:*:macos:*:*
- cpe:2.3:a:microsoft:office_long_term_servicing_channel:2021:*:*:*:*:-:x64:*
- cpe:2.3:a:microsoft:office_long_term_servicing_channel:2021:*:*:*:*:-:x86:*
- cpe:2.3:a:microsoft:office_long_term_servicing_channel:2024:*:*:*:*:macos:*:*
- cpe:2.3:a:microsoft:office_long_term_servicing_channel:2024:*:*:*:*:-:x64:*
- cpe:2.3:a:microsoft:office_long_term_servicing_channel:2024:*:*:*:*:-:x86:*
Patches
Vulnerability mechanics
References
1- msrc.microsoft.com/update-guide/vulnerability/CVE-2026-40358nvdVendor Advisory
News mentions
3- Microsoft Patch Tuesday for May 2026 — Snort rules and prominent vulnerabilitiesCisco Talos Intelligence · May 12, 2026
- Microsoft May 2026 Patch Tuesday fixes 120 flaws, no zero-daysBleepingComputer · May 12, 2026
- May 2026 Patch Tuesday: 30 Critical Vulnerabilities Among 130 CVEsCrowdStrike Blog