How severe is CVE-2018-8627?

CVE-2018-8627 has a CVSS 3.x base score of 5.5, rated medium severity. It is exploitable over local access with low attack complexity, requires no privileges and user interaction. Impact on confidentiality is high, integrity none, and availability none.

Is CVE-2018-8627 being actively exploited?

It is not currently listed in CISA's KEV catalog. Its EPSS exploit-prediction score is 9% (94th percentile), an estimate of the probability of exploitation in the next 30 days.

What products are affected by CVE-2018-8627?

CVE-2018-8627 primarily affects Microsoft Excel. In total, 12 product configurations (CPEs) are listed as vulnerable; see the affected-products list for the exact versions.

How do I fix CVE-2018-8627?

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

When was CVE-2018-8627 published?

CVE-2018-8627 was published on 2018-12-12 and last updated on 2026-06-17.

CVE-2018-8627

CVE-2018-8627 is a medium-severity vulnerability in Microsoft Excel with a CVSS 3.x base score of 5.5. 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-908.

Key facts

Severity: Medium (CVSS 3.x base score 5.5)
CVSS v2: 4.3
EPSS exploit prediction: 9% (94th percentile)
Actively exploited: Not listed in CISA KEV
Weakness: CWE-908
Affected product: Microsoft Excel
Published: 2018-12-12
Last modified: 2026-06-17

Description

An information disclosure vulnerability exists when Microsoft Excel software reads out of bound memory due to an uninitialized variable, which could disclose the contents of memory, aka "Microsoft Excel Information Disclosure Vulnerability." This affects Microsoft Office, Office 365 ProPlus, Microsoft Excel, Microsoft Excel Viewer, Excel. This CVE ID is unique from CVE-2018-8598.

Frequently asked questions

What is CVE-2018-8627?: An information disclosure vulnerability exists when Microsoft Excel software reads out of bound memory due to an uninitialized variable, which could disclose the contents of memory, aka "Microsoft Excel Information Disclosure Vulnerability." This affects Microsoft Office, Office 365 ProPlus, Microsoft Excel, Microsoft Excel Viewer, Excel. This CVE ID is unique from CVE-2018-8598.
How severe is CVE-2018-8627?: CVE-2018-8627 has a CVSS 3.x base score of 5.5, rated medium severity. It is exploitable over local access with low attack complexity, requires no privileges and user interaction. Impact on confidentiality is high, integrity none, and availability none.
Is CVE-2018-8627 being actively exploited?: It is not currently listed in CISA's KEV catalog. Its EPSS exploit-prediction score is 9% (94th percentile), an estimate of the probability of exploitation in the next 30 days.
What products are affected by CVE-2018-8627?: CVE-2018-8627 primarily affects Microsoft Excel. In total, 12 product configurations (CPEs) are listed as vulnerable; see the affected-products list for the exact versions.
How do I fix CVE-2018-8627?: Review the linked vendor and NVD advisories for patched versions and mitigations, then upgrade or apply the recommended workaround.
When was CVE-2018-8627 published?: CVE-2018-8627 was published on 2018-12-12 and last updated on 2026-06-17.

References

Affected products (12)

cpe:2.3:a:microsoft:excel:2010:sp2:*:*:*:*:*:*
cpe:2.3:a:microsoft:excel:2013:sp1:*:*:*:*:*:*
cpe:2.3:a:microsoft:excel:2013:sp1:*:*:rt:*:*:*
cpe:2.3:a:microsoft:excel:2016:*:*:*:*:*:*:*
cpe:2.3:a:microsoft:excel_viewer:2007:sp3:*:*:*:*:*:*
cpe:2.3:a:microsoft:office:2010:sp2:*:*:*:*:*:*
cpe:2.3:a:microsoft:office:2016:*:*:*:*:mac_os_x:*:*
cpe:2.3:a:microsoft:office:2019:*:*:*:*:*:*:*
cpe:2.3:a:microsoft:office:2019:*:*:*:*:macos:*:*
cpe:2.3:a:microsoft:office_365_proplus:-:*:*:*:*:*:*:*
cpe:2.3:a:microsoft:office_compatibility_pack:-:sp3:*:*:*:*:*:*
cpe:2.3:a:microsoft:sharepoint_server:2010:sp2:*:*:*:*:*:*

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