How severe is CVE-2026-45466?

CVE-2026-45466 has a CVSS 3.x base score of 3.3, rated low severity. It is exploitable over local access with low attack complexity, requires no privileges and user interaction. Impact on confidentiality is low, integrity none, and availability none.

Is CVE-2026-45466 being actively exploited?

It is not currently listed in CISA's KEV catalog. Its EPSS exploit-prediction score is 0% (29th percentile), an estimate of the probability of exploitation in the next 30 days.

What products are affected by CVE-2026-45466?

CVE-2026-45466 primarily affects Microsoft 365 Apps. In total, 9 product configurations (CPEs) are listed as vulnerable; see the affected-products list for the exact versions.

How do I fix CVE-2026-45466?

Review the linked vendor and NVD advisories for patched versions and mitigations, then upgrade or apply the recommended workaround.

Does CVE-2026-45466 have an EU (EUVD) identifier?

Yes. CVE-2026-45466 is tracked in the ENISA EU Vulnerability Database (EUVD) as EUVD-2026-35672.

When was CVE-2026-45466 published?

CVE-2026-45466 was published on 2026-06-09 and last updated on 2026-06-19.

CVE-2026-45466

CVE-2026-45466 is a low-severity vulnerability in Microsoft 365 Apps with a CVSS 3.x base score of 3.3. It is not currently listed as actively exploited by CISA, and its EPSS exploit-prediction score is low. The underlying weakness is classified as CWE-122.

Key facts

Severity: Low (CVSS 3.x base score 3.3)
EPSS exploit prediction: 0% (29th percentile)
Actively exploited: Not listed in CISA KEV
EU (EUVD) id: EUVD-2026-35672
Weakness: CWE-122
Affected product: Microsoft 365 Apps
Published: 2026-06-09
Last modified: 2026-06-19

Description

Heap-based buffer overflow in Microsoft Office Word allows an unauthorized attacker to disclose information locally.

Frequently asked questions

What is CVE-2026-45466?: Heap-based buffer overflow in Microsoft Office Word allows an unauthorized attacker to disclose information locally.
How severe is CVE-2026-45466?: CVE-2026-45466 has a CVSS 3.x base score of 3.3, rated low severity. It is exploitable over local access with low attack complexity, requires no privileges and user interaction. Impact on confidentiality is low, integrity none, and availability none.
Is CVE-2026-45466 being actively exploited?: It is not currently listed in CISA's KEV catalog. Its EPSS exploit-prediction score is 0% (29th percentile), an estimate of the probability of exploitation in the next 30 days.
What products are affected by CVE-2026-45466?: CVE-2026-45466 primarily affects Microsoft 365 Apps. In total, 9 product configurations (CPEs) are listed as vulnerable; see the affected-products list for the exact versions.
How do I fix CVE-2026-45466?: Review the linked vendor and NVD advisories for patched versions and mitigations, then upgrade or apply the recommended workaround.
Does CVE-2026-45466 have an EU (EUVD) identifier?: Yes. CVE-2026-45466 is tracked in the ENISA EU Vulnerability Database (EUVD) as EUVD-2026-35672.
When was CVE-2026-45466 published?: CVE-2026-45466 was published on 2026-06-09 and last updated on 2026-06-19.

References

https://msrc.microsoft.com/update-guide/vulnerability/CVE-2026-45466

Affected products (9)

cpe:2.3:a:microsoft:365_apps:-:*:*:*:enterprise:*:x64:*
cpe:2.3:a:microsoft:365_apps:-:*:*:*:enterprise:*:x86:*
cpe:2.3:a:microsoft:microsoft_365:-:*:*:*:*:macos:*:*
cpe:2.3:a:microsoft:office_2021:-:*:*:*:ltsc:-:x64:*
cpe:2.3:a:microsoft:office_2021:-:*:*:*:ltsc:-:x86:*
cpe:2.3:a:microsoft:office_2021:-:*:*:*:ltsc:macos:-:*
cpe:2.3:a:microsoft:office_2024:-:*:*:*:ltsc:-:x64:*
cpe:2.3:a:microsoft:office_2024:-:*:*:*:ltsc:-:x86:*
cpe:2.3:a:microsoft:office_2024:-:*:*:*:ltsc:macos:-:*

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