How severe is CVE-2023-6869?

CVE-2023-6869 has a CVSS 3.x base score of 6.5, rated medium severity. It is exploitable over network with low attack complexity, requires no privileges and user interaction. Impact on confidentiality is none, integrity high, and availability none.

Is CVE-2023-6869 being actively exploited?

It is not currently listed in CISA's KEV catalog. Its EPSS exploit-prediction score is 1% (42nd percentile), an estimate of the probability of exploitation in the next 30 days.

What products are affected by CVE-2023-6869?

CVE-2023-6869 affects Mozilla Firefox. See the affected-products list for the exact vulnerable versions.

How do I fix CVE-2023-6869?

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

When was CVE-2023-6869 published?

CVE-2023-6869 was published on 2023-12-19 and last updated on 2026-06-17.

CVE-2023-6869

CVE-2023-6869 is a medium-severity vulnerability in Mozilla Firefox with a CVSS 3.x base score of 6.5. It is not currently listed as actively exploited by CISA, and its EPSS exploit-prediction score is low.

Key facts

Severity: Medium (CVSS 3.x base score 6.5)
EPSS exploit prediction: 1% (42nd percentile)
Actively exploited: Not listed in CISA KEV
Affected product: Mozilla Firefox
Published: 2023-12-19
Last modified: 2026-06-17

Description

A `<dialog>` element could have been manipulated to paint content outside of a sandboxed iframe. This could allow untrusted content to display under the guise of trusted content. This vulnerability affects Firefox < 121.

Frequently asked questions

What is CVE-2023-6869?: A `<dialog>` element could have been manipulated to paint content outside of a sandboxed iframe. This could allow untrusted content to display under the guise of trusted content. This vulnerability affects Firefox < 121.
How severe is CVE-2023-6869?: CVE-2023-6869 has a CVSS 3.x base score of 6.5, rated medium severity. It is exploitable over network with low attack complexity, requires no privileges and user interaction. Impact on confidentiality is none, integrity high, and availability none.
Is CVE-2023-6869 being actively exploited?: It is not currently listed in CISA's KEV catalog. Its EPSS exploit-prediction score is 1% (42nd percentile), an estimate of the probability of exploitation in the next 30 days.
What products are affected by CVE-2023-6869?: CVE-2023-6869 affects Mozilla Firefox. See the affected-products list for the exact vulnerable versions.
How do I fix CVE-2023-6869?: Review the linked vendor and NVD advisories for patched versions and mitigations, then upgrade or apply the recommended workaround.
When was CVE-2023-6869 published?: CVE-2023-6869 was published on 2023-12-19 and last updated on 2026-06-17.

References

Affected products (1)

cpe:2.3:a:mozilla:firefox:*:*:*:*:*:*:*:*

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