How severe is CVE-2018-8427?

CVE-2018-8427 has a CVSS 3.x base score of 5.5, rated medium severity. It is exploitable over local access with low attack complexity, requires low privileges and no user interaction. Impact on confidentiality is high, integrity none, and availability none.

Is CVE-2018-8427 being actively exploited?

It is not currently listed in CISA's KEV catalog. Its EPSS exploit-prediction score is 2% (81st percentile), an estimate of the probability of exploitation in the next 30 days.

What products are affected by CVE-2018-8427?

CVE-2018-8427 primarily affects Microsoft Excel Viewer. In total, 8 product configurations (CPEs) are listed as vulnerable; see the affected-products list for the exact versions.

How do I fix CVE-2018-8427?

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

When was CVE-2018-8427 published?

CVE-2018-8427 was published on 2018-10-10 and last updated on 2026-06-17.

CVE-2018-8427

CVE-2018-8427 is a medium-severity vulnerability in Microsoft Excel Viewer 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-200.

Key facts

Severity: Medium (CVSS 3.x base score 5.5)
CVSS v2: 2.1
EPSS exploit prediction: 2% (81st percentile)
Actively exploited: Not listed in CISA KEV
Weakness: CWE-200
Affected product: Microsoft Excel Viewer
Published: 2018-10-10
Last modified: 2026-06-17

Description

An information disclosure vulnerability exists in the way that Microsoft Graphics Components handle objects in memory, aka "Microsoft Graphics Components Information Disclosure Vulnerability." This affects Microsoft Office, Microsoft Office Word Viewer, Office 365 ProPlus, Windows Server 2008, Microsoft PowerPoint Viewer, Microsoft Excel Viewer.

Frequently asked questions

What is CVE-2018-8427?: An information disclosure vulnerability exists in the way that Microsoft Graphics Components handle objects in memory, aka "Microsoft Graphics Components Information Disclosure Vulnerability." This affects Microsoft Office, Microsoft Office Word Viewer, Office 365 ProPlus, Windows Server 2008, Microsoft PowerPoint Viewer, Microsoft Excel Viewer.
How severe is CVE-2018-8427?: CVE-2018-8427 has a CVSS 3.x base score of 5.5, rated medium severity. It is exploitable over local access with low attack complexity, requires low privileges and no user interaction. Impact on confidentiality is high, integrity none, and availability none.
Is CVE-2018-8427 being actively exploited?: It is not currently listed in CISA's KEV catalog. Its EPSS exploit-prediction score is 2% (81st percentile), an estimate of the probability of exploitation in the next 30 days.
What products are affected by CVE-2018-8427?: CVE-2018-8427 primarily affects Microsoft Excel Viewer. In total, 8 product configurations (CPEs) are listed as vulnerable; see the affected-products list for the exact versions.
How do I fix CVE-2018-8427?: Review the linked vendor and NVD advisories for patched versions and mitigations, then upgrade or apply the recommended workaround.
When was CVE-2018-8427 published?: CVE-2018-8427 was published on 2018-10-10 and last updated on 2026-06-17.

References

Affected products (8)

cpe:2.3:a:microsoft:excel_viewer:2007:sp3:*:*:*:*:*:*
cpe:2.3:a:microsoft:office:2016:*:*:*:*:mac_os_x:*:*
cpe:2.3:a:microsoft:office:2019:*:*:*:*:*:*:*
cpe:2.3:a:microsoft:office_365_proplus:-:*:*:*:*:*:*:*
cpe:2.3:a:microsoft:office_compatibility_pack:-:sp3:*:*:*:*:*:*
cpe:2.3:a:microsoft:office_word_viewer:-:*:*:*:*:*:*:*
cpe:2.3:a:microsoft:powerpoint_viewer:2007:*:*:*:*:*:*:*
cpe:2.3:o:microsoft:windows_server_2008:-:sp2:*:*:*:*:*:*

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