How severe is CVE-2023-5729?

CVE-2023-5729 has a CVSS 3.x base score of 4.3, rated medium severity. It is exploitable over network with low attack complexity, requires no privileges and user interaction. Impact on confidentiality is none, integrity low, and availability none.

Is CVE-2023-5729 being actively exploited?

It is not currently listed in CISA's KEV catalog. Its EPSS exploit-prediction score is 1% (44th percentile), an estimate of the probability of exploitation in the next 30 days.

What products are affected by CVE-2023-5729?

CVE-2023-5729 affects Mozilla Firefox. See the affected-products list for the exact vulnerable versions.

How do I fix CVE-2023-5729?

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

When was CVE-2023-5729 published?

CVE-2023-5729 was published on 2023-10-25 and last updated on 2026-06-17.

CVE-2023-5729

CVE-2023-5729 is a medium-severity vulnerability in Mozilla Firefox with a CVSS 3.x base score of 4.3. 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 4.3)
EPSS exploit prediction: 1% (44th percentile)
Actively exploited: Not listed in CISA KEV
Affected product: Mozilla Firefox
Published: 2023-10-25
Last modified: 2026-06-17

Description

A malicious web site can enter fullscreen mode while simultaneously triggering a WebAuthn prompt. This could have obscured the fullscreen notification and could have been leveraged in a spoofing attack. This vulnerability affects Firefox < 119.

Frequently asked questions

What is CVE-2023-5729?: A malicious web site can enter fullscreen mode while simultaneously triggering a WebAuthn prompt. This could have obscured the fullscreen notification and could have been leveraged in a spoofing attack. This vulnerability affects Firefox < 119.
How severe is CVE-2023-5729?: CVE-2023-5729 has a CVSS 3.x base score of 4.3, rated medium severity. It is exploitable over network with low attack complexity, requires no privileges and user interaction. Impact on confidentiality is none, integrity low, and availability none.
Is CVE-2023-5729 being actively exploited?: It is not currently listed in CISA's KEV catalog. Its EPSS exploit-prediction score is 1% (44th percentile), an estimate of the probability of exploitation in the next 30 days.
What products are affected by CVE-2023-5729?: CVE-2023-5729 affects Mozilla Firefox. See the affected-products list for the exact vulnerable versions.
How do I fix CVE-2023-5729?: Review the linked vendor and NVD advisories for patched versions and mitigations, then upgrade or apply the recommended workaround.
When was CVE-2023-5729 published?: CVE-2023-5729 was published on 2023-10-25 and last updated on 2026-06-17.

References

Affected products (1)

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

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