How severe is CVE-2022-45420?

CVE-2022-45420 has a CVSS 3.x base score of 6.5, rated medium severity. It is exploitable over network with low attack complexity, requires no privileges and user interaction. Impact on confidentiality is none, integrity high, and availability none.

Is CVE-2022-45420 being actively exploited?

It is not currently listed in CISA's KEV catalog. Its EPSS exploit-prediction score is 1% (43rd percentile), an estimate of the probability of exploitation in the next 30 days.

What products are affected by CVE-2022-45420?

CVE-2022-45420 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-2022-45420?

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

When was CVE-2022-45420 published?

CVE-2022-45420 was published on 2022-12-22 and last updated on 2026-06-17.

CVE-2022-45420

CVE-2022-45420 is a medium-severity vulnerability in Mozilla Firefox with a CVSS 3.x base score of 6.5. 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-1021.

Key facts

Severity: Medium (CVSS 3.x base score 6.5)
EPSS exploit prediction: 1% (43rd percentile)
Actively exploited: Not listed in CISA KEV
Weakness: CWE-1021
Affected product: Mozilla Firefox
Published: 2022-12-22
Last modified: 2026-06-17

Description

Use tables inside of an iframe, an attacker could have caused iframe contents to be rendered outside the boundaries of the iframe, resulting in potential user confusion or spoofing attacks. This vulnerability affects Firefox ESR < 102.5, Thunderbird < 102.5, and Firefox < 107.

Frequently asked questions

What is CVE-2022-45420?: Use tables inside of an iframe, an attacker could have caused iframe contents to be rendered outside the boundaries of the iframe, resulting in potential user confusion or spoofing attacks. This vulnerability affects Firefox ESR < 102.5, Thunderbird < 102.5, and Firefox < 107.
How severe is CVE-2022-45420?: CVE-2022-45420 has a CVSS 3.x base score of 6.5, rated medium severity. It is exploitable over network with low attack complexity, requires no privileges and user interaction. Impact on confidentiality is none, integrity high, and availability none.
Is CVE-2022-45420 being actively exploited?: It is not currently listed in CISA's KEV catalog. Its EPSS exploit-prediction score is 1% (43rd percentile), an estimate of the probability of exploitation in the next 30 days.
What products are affected by CVE-2022-45420?: CVE-2022-45420 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-2022-45420?: Review the linked vendor and NVD advisories for patched versions and mitigations, then upgrade or apply the recommended workaround.
When was CVE-2022-45420 published?: CVE-2022-45420 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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