How severe is CVE-2024-3856?

CVE-2024-3856 has a CVSS 3.x base score of 8.8, rated high severity. It is exploitable over network with low attack complexity, requires no privileges and user interaction. Impact on confidentiality is high, integrity high, and availability high.

Is CVE-2024-3856 being actively exploited?

It is not currently listed in CISA's KEV catalog. Its EPSS exploit-prediction score is 1% (45th percentile), an estimate of the probability of exploitation in the next 30 days.

What products are affected by CVE-2024-3856?

CVE-2024-3856 affects Mozilla Firefox. See the affected-products list for the exact vulnerable versions.

How do I fix CVE-2024-3856?

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-2024-3856 have an EU (EUVD) identifier?

Yes. CVE-2024-3856 is tracked in the ENISA EU Vulnerability Database (EUVD) as EUVD-2024-32424.

When was CVE-2024-3856 published?

CVE-2024-3856 was published on 2024-04-16 and last updated on 2026-06-17.

CVE-2024-3856

CVE-2024-3856 is a high-severity vulnerability in Mozilla Firefox with a CVSS 3.x base score of 8.8. 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-416.

Key facts

Severity: High (CVSS 3.x base score 8.8)
EPSS exploit prediction: 1% (45th percentile)
Actively exploited: Not listed in CISA KEV
EU (EUVD) id: EUVD-2024-32424
Weakness: CWE-416
Affected product: Mozilla Firefox
Published: 2024-04-16
Last modified: 2026-06-17

Description

A use-after-free could occur during WASM execution if garbage collection ran during the creation of an array. This vulnerability affects Firefox < 125.

Frequently asked questions

What is CVE-2024-3856?: A use-after-free could occur during WASM execution if garbage collection ran during the creation of an array. This vulnerability affects Firefox < 125.
How severe is CVE-2024-3856?: CVE-2024-3856 has a CVSS 3.x base score of 8.8, rated high severity. It is exploitable over network with low attack complexity, requires no privileges and user interaction. Impact on confidentiality is high, integrity high, and availability high.
Is CVE-2024-3856 being actively exploited?: It is not currently listed in CISA's KEV catalog. Its EPSS exploit-prediction score is 1% (45th percentile), an estimate of the probability of exploitation in the next 30 days.
What products are affected by CVE-2024-3856?: CVE-2024-3856 affects Mozilla Firefox. See the affected-products list for the exact vulnerable versions.
How do I fix CVE-2024-3856?: 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-2024-3856 have an EU (EUVD) identifier?: Yes. CVE-2024-3856 is tracked in the ENISA EU Vulnerability Database (EUVD) as EUVD-2024-32424.
When was CVE-2024-3856 published?: CVE-2024-3856 was published on 2024-04-16 and last updated on 2026-06-17.

References

Affected products (1)

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

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