How severe is CVE-2024-3859?

CVE-2024-3859 has a CVSS 3.x base score of 5.9, rated medium severity. It is exploitable over network with high attack complexity, requires no privileges and user interaction. Impact on confidentiality is low, integrity high, and availability none.

Is CVE-2024-3859 being actively exploited?

It is not currently listed in CISA's KEV catalog. Its EPSS exploit-prediction score is 1% (47th percentile), an estimate of the probability of exploitation in the next 30 days.

What products are affected by CVE-2024-3859?

CVE-2024-3859 primarily affects Mozilla Firefox. In total, 4 product configurations (CPEs) are listed as vulnerable; see the affected-products list for the exact versions.

How do I fix CVE-2024-3859?

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

Does CVE-2024-3859 have an EU (EUVD) identifier?

Yes. CVE-2024-3859 is tracked in the ENISA EU Vulnerability Database (EUVD) as EUVD-2024-32427.

When was CVE-2024-3859 published?

CVE-2024-3859 was published on 2024-04-16 and last updated on 2026-06-17.

CVE-2024-3859

CVE-2024-3859 is a medium-severity vulnerability in Mozilla Firefox with a CVSS 3.x base score of 5.9. 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-125.

Key facts

Severity: Medium (CVSS 3.x base score 5.9)
EPSS exploit prediction: 1% (47th percentile)
Actively exploited: Not listed in CISA KEV
EU (EUVD) id: EUVD-2024-32427
Weakness: CWE-125
Affected product: Mozilla Firefox
Published: 2024-04-16
Last modified: 2026-06-17

Description

On 32-bit versions there were integer-overflows that led to an out-of-bounds-read that potentially could be triggered by a malformed OpenType font. This vulnerability affects Firefox < 125, Firefox ESR < 115.10, and Thunderbird < 115.10.

Frequently asked questions

What is CVE-2024-3859?: On 32-bit versions there were integer-overflows that led to an out-of-bounds-read that potentially could be triggered by a malformed OpenType font. This vulnerability affects Firefox < 125, Firefox ESR < 115.10, and Thunderbird < 115.10.
How severe is CVE-2024-3859?: CVE-2024-3859 has a CVSS 3.x base score of 5.9, rated medium severity. It is exploitable over network with high attack complexity, requires no privileges and user interaction. Impact on confidentiality is low, integrity high, and availability none.
Is CVE-2024-3859 being actively exploited?: It is not currently listed in CISA's KEV catalog. Its EPSS exploit-prediction score is 1% (47th percentile), an estimate of the probability of exploitation in the next 30 days.
What products are affected by CVE-2024-3859?: CVE-2024-3859 primarily affects Mozilla Firefox. In total, 4 product configurations (CPEs) are listed as vulnerable; see the affected-products list for the exact versions.
How do I fix CVE-2024-3859?: Review the linked vendor and NVD advisories for patched versions and mitigations, then upgrade or apply the recommended workaround.
Does CVE-2024-3859 have an EU (EUVD) identifier?: Yes. CVE-2024-3859 is tracked in the ENISA EU Vulnerability Database (EUVD) as EUVD-2024-32427.
When was CVE-2024-3859 published?: CVE-2024-3859 was published on 2024-04-16 and last updated on 2026-06-17.

References

Affected products (4)

cpe:2.3:a:mozilla:firefox:*:*:*:*:esr:*:*:*
cpe:2.3:a:mozilla:firefox:*:*:*:*:*:*:*:*
cpe:2.3:a:mozilla:thunderbird:*:*:*:*:*:*:*:*
cpe:2.3:o:debian:debian_linux:10.0:*:*:*:*:*:*:*

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