How severe is CVE-2022-26384?

CVE-2022-26384 has a CVSS 3.x base score of 9.6, rated critical 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-2022-26384 being actively exploited?

It is not currently listed in CISA's KEV catalog. Its EPSS exploit-prediction score is 1% (56th percentile), an estimate of the probability of exploitation in the next 30 days.

What products are affected by CVE-2022-26384?

CVE-2022-26384 primarily affects Mozilla Firefox. In total, 3 product configurations (CPEs) are listed as vulnerable; see the affected-products list for the exact versions.

How do I fix CVE-2022-26384?

Review the linked vendor and NVD advisories for patched versions and mitigations, then upgrade or apply the recommended workaround. Given its critical severity, prioritise patching exposed systems.

When was CVE-2022-26384 published?

CVE-2022-26384 was published on 2022-12-22 and last updated on 2026-06-17.

CVE-2022-26384

CVE-2022-26384 is a critical-severity vulnerability in Mozilla Firefox with a CVSS 3.x base score of 9.6. 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-693.

Key facts

Severity: Critical (CVSS 3.x base score 9.6)
EPSS exploit prediction: 1% (56th percentile)
Actively exploited: Not listed in CISA KEV
Weakness: CWE-693
Affected product: Mozilla Firefox
Published: 2022-12-22
Last modified: 2026-06-17

Description

If an attacker could control the contents of an iframe sandboxed with <code>allow-popups</code> but not <code>allow-scripts</code>, they were able to craft a link that, when clicked, would lead to JavaScript execution in violation of the sandbox. This vulnerability affects Firefox < 98, Firefox ESR < 91.7, and Thunderbird < 91.7.

Frequently asked questions

What is CVE-2022-26384?: If an attacker could control the contents of an iframe sandboxed with <code>allow-popups</code> but not <code>allow-scripts</code>, they were able to craft a link that, when clicked, would lead to JavaScript execution in violation of the sandbox. This vulnerability affects Firefox < 98, Firefox ESR < 91.7, and Thunderbird < 91.7.
How severe is CVE-2022-26384?: CVE-2022-26384 has a CVSS 3.x base score of 9.6, rated critical 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-2022-26384 being actively exploited?: It is not currently listed in CISA's KEV catalog. Its EPSS exploit-prediction score is 1% (56th percentile), an estimate of the probability of exploitation in the next 30 days.
What products are affected by CVE-2022-26384?: CVE-2022-26384 primarily affects Mozilla Firefox. In total, 3 product configurations (CPEs) are listed as vulnerable; see the affected-products list for the exact versions.
How do I fix CVE-2022-26384?: Review the linked vendor and NVD advisories for patched versions and mitigations, then upgrade or apply the recommended workaround. Given its critical severity, prioritise patching exposed systems.
When was CVE-2022-26384 published?: CVE-2022-26384 was published on 2022-12-22 and last updated on 2026-06-17.

References

Affected products (3)

cpe:2.3:a:mozilla:firefox:*:*:*:*:*:*:*:*
cpe:2.3:a:mozilla:firefox_esr:*:*:*:*:*:*:*:*
cpe:2.3:a:mozilla:thunderbird:*:*:*:*:*:*:*:*

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