How severe is CVE-2020-12412?

CVE-2020-12412 has a CVSS 3.x base score of 4.3, rated medium severity. It is exploitable over network with low attack complexity, requires no privileges and user interaction. Impact on confidentiality is none, integrity low, and availability none.

Is CVE-2020-12412 being actively exploited?

It is not currently listed in CISA's KEV catalog. Its EPSS exploit-prediction score is 1% (51st percentile), an estimate of the probability of exploitation in the next 30 days.

What products are affected by CVE-2020-12412?

CVE-2020-12412 affects Mozilla Firefox. See the affected-products list for the exact vulnerable versions.

How do I fix CVE-2020-12412?

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

When was CVE-2020-12412 published?

CVE-2020-12412 was published on 2020-07-09 and last updated on 2026-06-17.

CVE-2020-12412

CVE-2020-12412 is a medium-severity vulnerability in Mozilla Firefox with a CVSS 3.x base score of 4.3. It is not currently listed as actively exploited by CISA, and its EPSS exploit-prediction score is low.

Key facts

Severity: Medium (CVSS 3.x base score 4.3)
CVSS v2: 4.3
EPSS exploit prediction: 1% (51st percentile)
Actively exploited: Not listed in CISA KEV
Affected product: Mozilla Firefox
Published: 2020-07-09
Last modified: 2026-06-17

Description

By navigating a tab using the history API, an attacker could cause the address bar to display the incorrect domain (with the https:// scheme, a blocked port number such as '1', and without a lock icon) while controlling the page contents. This vulnerability affects Firefox < 70.

Frequently asked questions

What is CVE-2020-12412?: By navigating a tab using the history API, an attacker could cause the address bar to display the incorrect domain (with the https:// scheme, a blocked port number such as '1', and without a lock icon) while controlling the page contents. This vulnerability affects Firefox < 70.
How severe is CVE-2020-12412?: CVE-2020-12412 has a CVSS 3.x base score of 4.3, rated medium severity. It is exploitable over network with low attack complexity, requires no privileges and user interaction. Impact on confidentiality is none, integrity low, and availability none.
Is CVE-2020-12412 being actively exploited?: It is not currently listed in CISA's KEV catalog. Its EPSS exploit-prediction score is 1% (51st percentile), an estimate of the probability of exploitation in the next 30 days.
What products are affected by CVE-2020-12412?: CVE-2020-12412 affects Mozilla Firefox. See the affected-products list for the exact vulnerable versions.
How do I fix CVE-2020-12412?: Review the linked vendor and NVD advisories for patched versions and mitigations, then upgrade or apply the recommended workaround.
When was CVE-2020-12412 published?: CVE-2020-12412 was published on 2020-07-09 and last updated on 2026-06-17.

References

Affected products (1)

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

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