How severe is CVE-2024-1563?

CVE-2024-1563 has a CVSS 3.x base score of 8.1, rated high severity. It is exploitable over network with high attack complexity, requires no privileges and no user interaction. Impact on confidentiality is high, integrity high, and availability high.

Is CVE-2024-1563 being actively exploited?

It is not currently listed in CISA's KEV catalog. Its EPSS exploit-prediction score is 0% (31st percentile), an estimate of the probability of exploitation in the next 30 days.

What products are affected by CVE-2024-1563?

CVE-2024-1563 affects Mozilla Firefox Focus. See the affected-products list for the exact vulnerable versions.

How do I fix CVE-2024-1563?

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.

Does CVE-2024-1563 have an EU (EUVD) identifier?

Yes. CVE-2024-1563 is tracked in the ENISA EU Vulnerability Database (EUVD) as EUVD-2024-17307.

When was CVE-2024-1563 published?

CVE-2024-1563 was published on 2024-02-22 and last updated on 2026-06-17.

CVE-2024-1563

CVE-2024-1563 is a high-severity vulnerability in Mozilla Firefox Focus with a CVSS 3.x base score of 8.1. 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-367.

Key facts

Severity: High (CVSS 3.x base score 8.1)
EPSS exploit prediction: 0% (31st percentile)
Actively exploited: Not listed in CISA KEV
EU (EUVD) id: EUVD-2024-17307
Weakness: CWE-367
Affected product: Mozilla Firefox Focus
Published: 2024-02-22
Last modified: 2026-06-17

Description

An attacker could have executed unauthorized scripts on top origin sites using a JavaScript URI when opening an external URL with a custom Firefox scheme and a timeout race condition. This vulnerability affects Focus for iOS < 122.

Frequently asked questions

What is CVE-2024-1563?: An attacker could have executed unauthorized scripts on top origin sites using a JavaScript URI when opening an external URL with a custom Firefox scheme and a timeout race condition. This vulnerability affects Focus for iOS < 122.
How severe is CVE-2024-1563?: CVE-2024-1563 has a CVSS 3.x base score of 8.1, rated high severity. It is exploitable over network with high attack complexity, requires no privileges and no user interaction. Impact on confidentiality is high, integrity high, and availability high.
Is CVE-2024-1563 being actively exploited?: It is not currently listed in CISA's KEV catalog. Its EPSS exploit-prediction score is 0% (31st percentile), an estimate of the probability of exploitation in the next 30 days.
What products are affected by CVE-2024-1563?: CVE-2024-1563 affects Mozilla Firefox Focus. See the affected-products list for the exact vulnerable versions.
How do I fix CVE-2024-1563?: 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.
Does CVE-2024-1563 have an EU (EUVD) identifier?: Yes. CVE-2024-1563 is tracked in the ENISA EU Vulnerability Database (EUVD) as EUVD-2024-17307.
When was CVE-2024-1563 published?: CVE-2024-1563 was published on 2024-02-22 and last updated on 2026-06-17.

References

Affected products (1)

cpe:2.3:a:mozilla:firefox_focus:*:*:*:*:*:iphone_os:*:*

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