How severe is CVE-2026-12324?

CVE-2026-12324 has a CVSS 3.x base score of 7.3, rated high severity. It is exploitable over network with low attack complexity, requires no privileges and no user interaction. Impact on confidentiality is low, integrity low, and availability low.

Is CVE-2026-12324 being actively exploited?

It is not currently listed in CISA's KEV catalog. Its EPSS exploit-prediction score is 0% (11th percentile), an estimate of the probability of exploitation in the next 30 days.

What products are affected by CVE-2026-12324?

CVE-2026-12324 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-2026-12324?

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-2026-12324 have an EU (EUVD) identifier?

Yes. CVE-2026-12324 is tracked in the ENISA EU Vulnerability Database (EUVD) as EUVD-2026-37070.

When was CVE-2026-12324 published?

CVE-2026-12324 was published on 2026-06-16 and last updated on 2026-06-17.

CVE-2026-12324

CVE-2026-12324 is a high-severity vulnerability in Mozilla Firefox with a CVSS 3.x base score of 7.3. 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-703.

Key facts

Severity: High (CVSS 3.x base score 7.3)
EPSS exploit prediction: 0% (11th percentile)
Actively exploited: Not listed in CISA KEV
EU (EUVD) id: EUVD-2026-37070
Weakness: CWE-703
Affected product: Mozilla Firefox
Published: 2026-06-16
Last modified: 2026-06-17

Description

Incorrect boundary conditions in the Graphics: CanvasWebGL component. This vulnerability was fixed in Firefox 152, Firefox ESR 140.12, Thunderbird 152, and Thunderbird 140.12.

Frequently asked questions

What is CVE-2026-12324?: Incorrect boundary conditions in the Graphics: CanvasWebGL component. This vulnerability was fixed in Firefox 152, Firefox ESR 140.12, Thunderbird 152, and Thunderbird 140.12.
How severe is CVE-2026-12324?: CVE-2026-12324 has a CVSS 3.x base score of 7.3, rated high severity. It is exploitable over network with low attack complexity, requires no privileges and no user interaction. Impact on confidentiality is low, integrity low, and availability low.
Is CVE-2026-12324 being actively exploited?: It is not currently listed in CISA's KEV catalog. Its EPSS exploit-prediction score is 0% (11th percentile), an estimate of the probability of exploitation in the next 30 days.
What products are affected by CVE-2026-12324?: CVE-2026-12324 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-2026-12324?: 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-2026-12324 have an EU (EUVD) identifier?: Yes. CVE-2026-12324 is tracked in the ENISA EU Vulnerability Database (EUVD) as EUVD-2026-37070.
When was CVE-2026-12324 published?: CVE-2026-12324 was published on 2026-06-16 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:*:*:*:*:esr:*:*:*
cpe:2.3:a:mozilla:thunderbird:*:*:*:*:-:*:*:*

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