How severe is CVE-2017-8521?

CVE-2017-8521 has a CVSS 3.x base score of 7.5, rated high severity. It is exploitable over network with high attack complexity, requires no privileges and user interaction. Impact on confidentiality is high, integrity high, and availability high.

Is CVE-2017-8521 being actively exploited?

It is not currently listed in CISA's KEV catalog. Its EPSS exploit-prediction score is 6% (93rd percentile), an estimate of the probability of exploitation in the next 30 days.

What products are affected by CVE-2017-8521?

CVE-2017-8521 affects Microsoft Edge. See the affected-products list for the exact vulnerable versions.

How do I fix CVE-2017-8521?

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-2017-8521 published?

CVE-2017-8521 was published on 2017-06-15 and last updated on 2026-06-17.

CVE-2017-8521

CVE-2017-8521 is a high-severity vulnerability in Microsoft Edge with a CVSS 3.x base score of 7.5. 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-119.

Key facts

Severity: High (CVSS 3.x base score 7.5)
CVSS v2: 7.6
EPSS exploit prediction: 6% (93rd percentile)
Actively exploited: Not listed in CISA KEV
Weakness: CWE-119
Affected product: Microsoft Edge
Published: 2017-06-15
Last modified: 2026-06-17

Description

Microsoft Edge in Windows 10 1703 allows an attacker to execute arbitrary code in the context of the current user when the Edge JavaScript scripting engine fails to handle objects in memory, aka "Scripting Engine Memory Corruption Vulnerability". This CVE ID is unique from CVE-2017-8499, CVE-2017-8520, CVE-2017-8548, and CVE-2017-8549.

Frequently asked questions

What is CVE-2017-8521?: Microsoft Edge in Windows 10 1703 allows an attacker to execute arbitrary code in the context of the current user when the Edge JavaScript scripting engine fails to handle objects in memory, aka "Scripting Engine Memory Corruption Vulnerability". This CVE ID is unique from CVE-2017-8499, CVE-2017-8520, CVE-2017-8548, and CVE-2017-8549.
How severe is CVE-2017-8521?: CVE-2017-8521 has a CVSS 3.x base score of 7.5, rated high severity. It is exploitable over network with high attack complexity, requires no privileges and user interaction. Impact on confidentiality is high, integrity high, and availability high.
Is CVE-2017-8521 being actively exploited?: It is not currently listed in CISA's KEV catalog. Its EPSS exploit-prediction score is 6% (93rd percentile), an estimate of the probability of exploitation in the next 30 days.
What products are affected by CVE-2017-8521?: CVE-2017-8521 affects Microsoft Edge. See the affected-products list for the exact vulnerable versions.
How do I fix CVE-2017-8521?: 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-2017-8521 published?: CVE-2017-8521 was published on 2017-06-15 and last updated on 2026-06-17.

References

Affected products (1)

cpe:2.3:a:microsoft:edge:*:*:*:*:*:*:*:*

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