How severe is CVE-2021-28465?

CVE-2021-28465 has a CVSS 3.x base score of 7.8, rated high severity. It is exploitable over local access with low attack complexity, requires no privileges and user interaction. Impact on confidentiality is high, integrity high, and availability high.

Is CVE-2021-28465 being actively exploited?

It is not currently listed in CISA's KEV catalog. Its EPSS exploit-prediction score is 4% (88th percentile), an estimate of the probability of exploitation in the next 30 days.

What products are affected by CVE-2021-28465?

CVE-2021-28465 affects Microsoft Web Media Extensions. See the affected-products list for the exact vulnerable versions.

How do I fix CVE-2021-28465?

Review the linked vendor and NVD advisories for patched versions and mitigations, then upgrade or apply the recommended workaround. Given its high severity, prioritise patching exposed systems.

When was CVE-2021-28465 published?

CVE-2021-28465 was published on 2021-05-11 and last updated on 2026-06-17.

CVE-2021-28465

CVE-2021-28465 is a high-severity vulnerability in Microsoft Web Media Extensions with a CVSS 3.x base score of 7.8. 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-787.

Key facts

Severity: High (CVSS 3.x base score 7.8)
CVSS v2: 6.8
EPSS exploit prediction: 4% (88th percentile)
Actively exploited: Not listed in CISA KEV
Weakness: CWE-787
Affected product: Microsoft Web Media Extensions
Published: 2021-05-11
Last modified: 2026-06-17

Description

Web Media Extensions Remote Code Execution Vulnerability

Frequently asked questions

What is CVE-2021-28465?: Web Media Extensions Remote Code Execution Vulnerability
How severe is CVE-2021-28465?: CVE-2021-28465 has a CVSS 3.x base score of 7.8, rated high severity. It is exploitable over local access with low attack complexity, requires no privileges and user interaction. Impact on confidentiality is high, integrity high, and availability high.
Is CVE-2021-28465 being actively exploited?: It is not currently listed in CISA's KEV catalog. Its EPSS exploit-prediction score is 4% (88th percentile), an estimate of the probability of exploitation in the next 30 days.
What products are affected by CVE-2021-28465?: CVE-2021-28465 affects Microsoft Web Media Extensions. See the affected-products list for the exact vulnerable versions.
How do I fix CVE-2021-28465?: Review the linked vendor and NVD advisories for patched versions and mitigations, then upgrade or apply the recommended workaround. Given its high severity, prioritise patching exposed systems.
When was CVE-2021-28465 published?: CVE-2021-28465 was published on 2021-05-11 and last updated on 2026-06-17.

References

Affected products (1)

cpe:2.3:a:microsoft:web_media_extensions:-:*:*:*:*:*:*:*

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