How severe is CVE-2023-21720?

CVE-2023-21720 has a CVSS 3.x base score of 5.3, rated medium severity. It is exploitable over network with high attack complexity, requires no privileges and user interaction. Impact on confidentiality is none, integrity none, and availability high.

Is CVE-2023-21720 being actively exploited?

It is not currently listed in CISA's KEV catalog. Its EPSS exploit-prediction score is 1% (65th percentile), an estimate of the probability of exploitation in the next 30 days.

What products are affected by CVE-2023-21720?

CVE-2023-21720 affects Microsoft Edge Chromium. See the affected-products list for the exact vulnerable versions.

How do I fix CVE-2023-21720?

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

When was CVE-2023-21720 published?

CVE-2023-21720 was published on 2023-02-14 and last updated on 2026-06-17.

CVE-2023-21720

CVE-2023-21720 is a medium-severity vulnerability in Microsoft Edge Chromium with a CVSS 3.x base score of 5.3. 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-126.

Key facts

Severity: Medium (CVSS 3.x base score 5.3)
EPSS exploit prediction: 1% (65th percentile)
Actively exploited: Not listed in CISA KEV
Weakness: CWE-126
Affected product: Microsoft Edge Chromium
Published: 2023-02-14
Last modified: 2026-06-17

Description

Microsoft Edge (Chromium-based) Tampering Vulnerability

Frequently asked questions

What is CVE-2023-21720?: Microsoft Edge (Chromium-based) Tampering Vulnerability
How severe is CVE-2023-21720?: CVE-2023-21720 has a CVSS 3.x base score of 5.3, rated medium severity. It is exploitable over network with high attack complexity, requires no privileges and user interaction. Impact on confidentiality is none, integrity none, and availability high.
Is CVE-2023-21720 being actively exploited?: It is not currently listed in CISA's KEV catalog. Its EPSS exploit-prediction score is 1% (65th percentile), an estimate of the probability of exploitation in the next 30 days.
What products are affected by CVE-2023-21720?: CVE-2023-21720 affects Microsoft Edge Chromium. See the affected-products list for the exact vulnerable versions.
How do I fix CVE-2023-21720?: Review the linked vendor and NVD advisories for patched versions and mitigations, then upgrade or apply the recommended workaround.
When was CVE-2023-21720 published?: CVE-2023-21720 was published on 2023-02-14 and last updated on 2026-06-17.

References

Affected products (1)

cpe:2.3:a:microsoft:edge_chromium:*:*:*:*:*:*:*:*

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