How severe is CVE-2026-4722?

CVE-2026-4722 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-2026-4722 being actively exploited?

It is not currently listed in CISA's KEV catalog. Its EPSS exploit-prediction score is 0% (23rd percentile), an estimate of the probability of exploitation in the next 30 days.

What products are affected by CVE-2026-4722?

CVE-2026-4722 affects Mozilla Firefox. See the affected-products list for the exact vulnerable versions.

How do I fix CVE-2026-4722?

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-2026-4722 have an EU (EUVD) identifier?

Yes. CVE-2026-4722 is tracked in the ENISA EU Vulnerability Database (EUVD) as EUVD-2026-14859.

When was CVE-2026-4722 published?

CVE-2026-4722 was published on 2026-03-24 and last updated on 2026-06-17.

CVE-2026-4722

CVE-2026-4722 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.

Key facts

Severity: High (CVSS 3.x base score 8.8)
EPSS exploit prediction: 0% (23rd percentile)
Actively exploited: Not listed in CISA KEV
EU (EUVD) id: EUVD-2026-14859
Affected product: Mozilla Firefox
Published: 2026-03-24
Last modified: 2026-06-17

Description

Privilege escalation in the IPC component. This vulnerability was fixed in Firefox 149 and Thunderbird 149.

Frequently asked questions

What is CVE-2026-4722?: Privilege escalation in the IPC component. This vulnerability was fixed in Firefox 149 and Thunderbird 149.
How severe is CVE-2026-4722?: CVE-2026-4722 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-2026-4722 being actively exploited?: It is not currently listed in CISA's KEV catalog. Its EPSS exploit-prediction score is 0% (23rd percentile), an estimate of the probability of exploitation in the next 30 days.
What products are affected by CVE-2026-4722?: CVE-2026-4722 affects Mozilla Firefox. See the affected-products list for the exact vulnerable versions.
How do I fix CVE-2026-4722?: 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-2026-4722 have an EU (EUVD) identifier?: Yes. CVE-2026-4722 is tracked in the ENISA EU Vulnerability Database (EUVD) as EUVD-2026-14859.
When was CVE-2026-4722 published?: CVE-2026-4722 was published on 2026-03-24 and last updated on 2026-06-17.

References

Affected products (1)

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

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