May 2026 Patch TuesdayMSRC-2026-05-microsoft-office-release-notesNormal patch window

Microsoft · MSRC-2026-05-microsoft-office-release-notes

Linked CVE review

Deploy Microsoft Microsoft Office update for Microsoft Office LTSC for Mac 2021

Linked CVEs: 11
Confirmed exploited: 0
PoC or lab evidence: 0
Maximum CVSS: 8.4

Evidence is kept separate

Confirmed exploitation, public exploit material, EPSS probability and CVSS severity answer different questions. “No confirmation recorded” means the checked sources do not currently confirm exploitation. It is not proof that exploitation has not occurred.

11 of 11 linked CVEs shown

Confirmed exploitedCVSS above 9.0

CVE and description	Severity	Exploit reality	Forecast and access	Remediation
CVE-2026-40359 Scheduled assessment Microsoft Excel Remote Code Execution Vulnerability Use after free in Microsoft Office Excel allows an unauthorized attacker to execute code locally.	7.8 · CVSS 3.1 · HighSource: CNA	No confirmation recordedNo CISA KEV match was present at the last successful refresh. This means no confirmation from that source, not proof of no exploitation.None recordedNo exploit-tagged reference or CISA SSVC proof-of-concept state is currently recorded. Research may still exist outside the structured feeds.	EPSS: 0.47% · 38.4th percentileForecast date: 2026-10-09LOCAL · LOW complexity · NONE privileges · REQUIRED user interaction	Within 7 daysHigh technical severity; prioritise exposed affected systems while verifying vendor guidance.Awaiting fix. No fixed version is explicitly recorded in the structured CVE data.
CVE-2026-40360 Scheduled assessment Microsoft Excel Information Disclosure Vulnerability Out-of-bounds read in Microsoft Office Excel allows an unauthorized attacker to disclose information locally.	7.8 · CVSS 3.1 · HighSource: CNA	No confirmation recordedNo CISA KEV match was present at the last successful refresh. This means no confirmation from that source, not proof of no exploitation.None recordedNo exploit-tagged reference or CISA SSVC proof-of-concept state is currently recorded. Research may still exist outside the structured feeds.	EPSS: 0.47% · 38.5th percentileForecast date: 2026-10-09LOCAL · LOW complexity · NONE privileges · REQUIRED user interaction	Within 7 daysHigh technical severity; prioritise exposed affected systems while verifying vendor guidance.Awaiting fix. No fixed version is explicitly recorded in the structured CVE data.
CVE-2026-40362 Scheduled assessment Microsoft Excel Remote Code Execution Vulnerability Use after free in Microsoft Office Excel allows an unauthorized attacker to execute code locally.	7.8 · CVSS 3.1 · HighSource: CNA	No confirmation recordedNo CISA KEV match was present at the last successful refresh. This means no confirmation from that source, not proof of no exploitation.None recordedNo exploit-tagged reference or CISA SSVC proof-of-concept state is currently recorded. Research may still exist outside the structured feeds.	EPSS: 0.47% · 38.4th percentileForecast date: 2026-10-09LOCAL · LOW complexity · NONE privileges · REQUIRED user interaction	Within 7 daysHigh technical severity; prioritise exposed affected systems while verifying vendor guidance.Awaiting fix. No fixed version is explicitly recorded in the structured CVE data.
CVE-2026-42831 Scheduled assessment Microsoft Office Remote Code Execution Vulnerability Heap-based buffer overflow in Microsoft Office allows an unauthorized attacker to execute code locally.	7.8 · CVSS 3.1 · HighSource: CNA	No confirmation recordedNo CISA KEV match was present at the last successful refresh. This means no confirmation from that source, not proof of no exploitation.None recordedNo exploit-tagged reference or CISA SSVC proof-of-concept state is currently recorded. Research may still exist outside the structured feeds.	EPSS: 0.47% · 38.5th percentileForecast date: 2026-10-09LOCAL · LOW complexity · NONE privileges · REQUIRED user interaction	Within 7 daysHigh technical severity; prioritise exposed affected systems while verifying vendor guidance.Awaiting fix. No fixed version is explicitly recorded in the structured CVE data.
CVE-2026-40367 Scheduled assessment Microsoft Word Remote Code Execution Vulnerability Access of resource using incompatible type ('type confusion') in Microsoft Office Word allows an unauthorized attacker to execute code locally.	8.4 · CVSS 3.1 · HighSource: CNA	No confirmation recordedNo CISA KEV match was present at the last successful refresh. This means no confirmation from that source, not proof of no exploitation.None recordedNo exploit-tagged reference or CISA SSVC proof-of-concept state is currently recorded. Research may still exist outside the structured feeds.	EPSS: 0.45% · 36.8th percentileForecast date: 2026-10-09LOCAL · LOW complexity · NONE privileges · NONE user interaction	Within 7 daysHigh technical severity; prioritise exposed affected systems while verifying vendor guidance.Awaiting fix. No fixed version is explicitly recorded in the structured CVE data.
CVE-2026-40358 Scheduled assessment Microsoft Office Remote Code Execution Vulnerability Heap-based buffer overflow in Microsoft Office allows an unauthorized attacker to execute code locally.	8.4 · CVSS 3.1 · HighSource: CNA	No confirmation recordedNo CISA KEV match was present at the last successful refresh. This means no confirmation from that source, not proof of no exploitation.None recordedNo exploit-tagged reference or CISA SSVC proof-of-concept state is currently recorded. Research may still exist outside the structured feeds.	EPSS: 0.36% · 28.2th percentileForecast date: 2026-10-09LOCAL · LOW complexity · NONE privileges · NONE user interaction	Within 7 daysHigh technical severity; prioritise exposed affected systems while verifying vendor guidance.Awaiting fix. No fixed version is explicitly recorded in the structured CVE data.
CVE-2026-40361 Scheduled assessment Microsoft Outlook and Word Remote Code Execution Vulnerability Use after free in Microsoft Office allows an unauthorized attacker to execute code locally.	8.4 · CVSS 3.1 · HighSource: CNA	No confirmation recordedNo CISA KEV match was present at the last successful refresh. This means no confirmation from that source, not proof of no exploitation.None recordedNo exploit-tagged reference or CISA SSVC proof-of-concept state is currently recorded. Research may still exist outside the structured feeds.	EPSS: 0.36% · 28.2th percentileForecast date: 2026-10-09LOCAL · LOW complexity · NONE privileges · NONE user interaction	Within 7 daysHigh technical severity; prioritise exposed affected systems while verifying vendor guidance.Awaiting fix. No fixed version is explicitly recorded in the structured CVE data.
CVE-2026-40363 Scheduled assessment Microsoft Office Remote Code Execution Vulnerability Heap-based buffer overflow in Microsoft Office allows an unauthorized attacker to execute code locally.	8.4 · CVSS 3.1 · HighSource: CNA	No confirmation recordedNo CISA KEV match was present at the last successful refresh. This means no confirmation from that source, not proof of no exploitation.None recordedNo exploit-tagged reference or CISA SSVC proof-of-concept state is currently recorded. Research may still exist outside the structured feeds.	EPSS: 0.36% · 28.2th percentileForecast date: 2026-10-09LOCAL · LOW complexity · NONE privileges · NONE user interaction	Within 7 daysHigh technical severity; prioritise exposed affected systems while verifying vendor guidance.Awaiting fix. No fixed version is explicitly recorded in the structured CVE data.
CVE-2026-40364 Scheduled assessment Microsoft Word Remote Code Execution Vulnerability Access of resource using incompatible type ('type confusion') in Microsoft Office Word allows an unauthorized attacker to execute code locally.	8.4 · CVSS 3.1 · HighSource: CNA	No confirmation recordedNo CISA KEV match was present at the last successful refresh. This means no confirmation from that source, not proof of no exploitation.None recordedNo exploit-tagged reference or CISA SSVC proof-of-concept state is currently recorded. Research may still exist outside the structured feeds.	EPSS: 0.36% · 28.2th percentileForecast date: 2026-10-09LOCAL · LOW complexity · NONE privileges · NONE user interaction	Within 7 daysHigh technical severity; prioritise exposed affected systems while verifying vendor guidance.Awaiting fix. No fixed version is explicitly recorded in the structured CVE data.
CVE-2026-40366 Scheduled assessment Microsoft Word Remote Code Execution Vulnerability Access of resource using incompatible type ('type confusion') in Microsoft Office Word allows an unauthorized attacker to execute code locally.	8.4 · CVSS 3.1 · HighSource: CNA	No confirmation recordedNo CISA KEV match was present at the last successful refresh. This means no confirmation from that source, not proof of no exploitation.None recordedNo exploit-tagged reference or CISA SSVC proof-of-concept state is currently recorded. Research may still exist outside the structured feeds.	EPSS: 0.36% · 28.2th percentileForecast date: 2026-10-09LOCAL · LOW complexity · NONE privileges · NONE user interaction	Within 7 daysHigh technical severity; prioritise exposed affected systems while verifying vendor guidance.Awaiting fix. No fixed version is explicitly recorded in the structured CVE data.
CVE-2026-42832 Scheduled assessment Microsoft Office Spoofing Vulnerability Improper access control in Microsoft Office allows an unauthorized attacker to perform spoofing locally.	7.7 · CVSS 3.1 · HighSource: CNA	No confirmation recordedNo CISA KEV match was present at the last successful refresh. This means no confirmation from that source, not proof of no exploitation.None recordedNo exploit-tagged reference or CISA SSVC proof-of-concept state is currently recorded. Research may still exist outside the structured feeds.	EPSS: 0.31% · 22.2th percentileForecast date: 2026-10-09LOCAL · LOW complexity · NONE privileges · NONE user interaction	Within 7 daysHigh technical severity; prioritise exposed affected systems while verifying vendor guidance.Awaiting fix. No fixed version is explicitly recorded in the structured CVE data.