How severe is CVE-2024-3861?

CVE-2024-3861 has a CVSS 3.x base score of 4.0, rated medium severity. It is exploitable over local access with low attack complexity, requires no privileges and no user interaction. Impact on confidentiality is low, integrity none, and availability none.

Is CVE-2024-3861 being actively exploited?

It is not currently listed in CISA's KEV catalog. Its EPSS exploit-prediction score is 0% (13th percentile), an estimate of the probability of exploitation in the next 30 days.

What products are affected by CVE-2024-3861?

CVE-2024-3861 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-2024-3861?

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

Does CVE-2024-3861 have an EU (EUVD) identifier?

Yes. CVE-2024-3861 is tracked in the ENISA EU Vulnerability Database (EUVD) as EUVD-2024-32429.

When was CVE-2024-3861 published?

CVE-2024-3861 was published on 2024-04-16 and last updated on 2026-06-17.

CVE-2024-3861

CVE-2024-3861 is a medium-severity vulnerability in Mozilla Firefox with a CVSS 3.x base score of 4.0. 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: Medium (CVSS 3.x base score 4.0)
EPSS exploit prediction: 0% (13th percentile)
Actively exploited: Not listed in CISA KEV
EU (EUVD) id: EUVD-2024-32429
Weakness: CWE-416
Affected product: Mozilla Firefox
Published: 2024-04-16
Last modified: 2026-06-17

Description

If an AlignedBuffer were assigned to itself, the subsequent self-move could result in an incorrect reference count and later use-after-free. This vulnerability affects Firefox < 125, Firefox ESR < 115.10, and Thunderbird < 115.10.

Frequently asked questions

What is CVE-2024-3861?: If an AlignedBuffer were assigned to itself, the subsequent self-move could result in an incorrect reference count and later use-after-free. This vulnerability affects Firefox < 125, Firefox ESR < 115.10, and Thunderbird < 115.10.
How severe is CVE-2024-3861?: CVE-2024-3861 has a CVSS 3.x base score of 4.0, rated medium severity. It is exploitable over local access with low attack complexity, requires no privileges and no user interaction. Impact on confidentiality is low, integrity none, and availability none.
Is CVE-2024-3861 being actively exploited?: It is not currently listed in CISA's KEV catalog. Its EPSS exploit-prediction score is 0% (13th percentile), an estimate of the probability of exploitation in the next 30 days.
What products are affected by CVE-2024-3861?: CVE-2024-3861 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-2024-3861?: Review the linked vendor and NVD advisories for patched versions and mitigations, then upgrade or apply the recommended workaround.
Does CVE-2024-3861 have an EU (EUVD) identifier?: Yes. CVE-2024-3861 is tracked in the ENISA EU Vulnerability Database (EUVD) as EUVD-2024-32429.
When was CVE-2024-3861 published?: CVE-2024-3861 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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