What is CVE-2023-29533?

A website could have obscured the fullscreen notification by using a combination of window.open , fullscreen requests, window.name assignments, and setInterval calls. This could have led to user confusion and possible spoofing attacks. This vulnerability affects Firefox < 112, Focus for Android < 112, Firefox ESR < 102.10, Firefox for Android < 112, and Thunderbird < 102.10.

How severe is CVE-2023-29533?

CVE-2023-29533 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-2023-29533 being actively exploited?

It is not currently listed in CISA's KEV catalog. Its EPSS exploit-prediction score is 1% (43rd percentile), an estimate of the probability of exploitation in the next 30 days.

What products are affected by CVE-2023-29533?

CVE-2023-29533 primarily affects Mozilla Firefox. In total, 5 product configurations (CPEs) are listed as vulnerable; see the affected-products list for the exact versions.

How do I fix CVE-2023-29533?

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

When was CVE-2023-29533 published?

CVE-2023-29533 was published on 2023-06-02 and last updated on 2026-06-17.

CVE-2023-29533

Q: How severe is CVE-2023-29533?

CVE-2023-29533 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.

Q: Is CVE-2023-29533 being actively exploited?

It is not currently listed in CISA's KEV catalog. Its EPSS exploit-prediction score is 1% (43rd percentile), an estimate of the probability of exploitation in the next 30 days.

Q: What products are affected by CVE-2023-29533?

CVE-2023-29533 primarily affects Mozilla Firefox. In total, 5 product configurations (CPEs) are listed as vulnerable; see the affected-products list for the exact versions.

Q: How do I fix CVE-2023-29533?

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

Q: When was CVE-2023-29533 published?

CVE-2023-29533 was published on 2023-06-02 and last updated on 2026-06-17.

CVE-2023-29533 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% (43rd percentile)
Actively exploited: Not listed in CISA KEV
Affected product: Mozilla Firefox
Published: 2023-06-02
Last modified: 2026-06-17

Description

A website could have obscured the fullscreen notification by using a combination of <code>window.open</code>, fullscreen requests, <code>window.name</code> assignments, and <code>setInterval</code> calls. This could have led to user confusion and possible spoofing attacks. This vulnerability affects Firefox < 112, Focus for Android < 112, Firefox ESR < 102.10, Firefox for Android < 112, and Thunderbird < 102.10.

Frequently asked questions

What is CVE-2023-29533?: A website could have obscured the fullscreen notification by using a combination of <code>window.open</code>, fullscreen requests, <code>window.name</code> assignments, and <code>setInterval</code> calls. This could have led to user confusion and possible spoofing attacks. This vulnerability affects Firefox < 112, Focus for Android < 112, Firefox ESR < 102.10, Firefox for Android < 112, and Thunderbird < 102.10.
How severe is CVE-2023-29533?: CVE-2023-29533 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-2023-29533 being actively exploited?: It is not currently listed in CISA's KEV catalog. Its EPSS exploit-prediction score is 1% (43rd percentile), an estimate of the probability of exploitation in the next 30 days.
What products are affected by CVE-2023-29533?: CVE-2023-29533 primarily affects Mozilla Firefox. In total, 5 product configurations (CPEs) are listed as vulnerable; see the affected-products list for the exact versions.
How do I fix CVE-2023-29533?: Review the linked vendor and NVD advisories for patched versions and mitigations, then upgrade or apply the recommended workaround.
When was CVE-2023-29533 published?: CVE-2023-29533 was published on 2023-06-02 and last updated on 2026-06-17.

References

Affected products (5)

cpe:2.3:a:mozilla:firefox:*:*:*:*:*:*:*:*
cpe:2.3:a:mozilla:firefox:*:*:*:*:*:android:*:*
cpe:2.3:a:mozilla:firefox_esr:*:*:*:*:*:*:*:*
cpe:2.3:a:mozilla:focus:*:*:*:*:*:android:*:*
cpe:2.3:a:mozilla:thunderbird:*:*:*:*:*:*:*:*

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