How severe is CVE-2020-12394?

CVE-2020-12394 has a CVSS 3.x base score of 3.3, rated low severity. It is exploitable over local access with low attack complexity, requires low privileges and no user interaction. Impact on confidentiality is none, integrity low, and availability none.

Is CVE-2020-12394 being actively exploited?

It is not currently listed in CISA's KEV catalog. Its EPSS exploit-prediction score is 0% (19th percentile), an estimate of the probability of exploitation in the next 30 days.

What products are affected by CVE-2020-12394?

CVE-2020-12394 affects Mozilla Firefox. See the affected-products list for the exact vulnerable versions.

How do I fix CVE-2020-12394?

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

When was CVE-2020-12394 published?

CVE-2020-12394 was published on 2020-05-26 and last updated on 2026-06-17.

CVE-2020-12394

CVE-2020-12394 is a low-severity vulnerability in Mozilla Firefox with a CVSS 3.x base score of 3.3. It is not currently listed as actively exploited by CISA, and its EPSS exploit-prediction score is low.

Key facts

Severity: Low (CVSS 3.x base score 3.3)
CVSS v2: 2.1
EPSS exploit prediction: 0% (19th percentile)
Actively exploited: Not listed in CISA KEV
Affected product: Mozilla Firefox
Published: 2020-05-26
Last modified: 2026-06-17

Description

A logic flaw in our location bar implementation could have allowed a local attacker to spoof the current location by selecting a different origin and removing focus from the input element. This vulnerability affects Firefox < 76.

Frequently asked questions

What is CVE-2020-12394?: A logic flaw in our location bar implementation could have allowed a local attacker to spoof the current location by selecting a different origin and removing focus from the input element. This vulnerability affects Firefox < 76.
How severe is CVE-2020-12394?: CVE-2020-12394 has a CVSS 3.x base score of 3.3, rated low severity. It is exploitable over local access with low attack complexity, requires low privileges and no user interaction. Impact on confidentiality is none, integrity low, and availability none.
Is CVE-2020-12394 being actively exploited?: It is not currently listed in CISA's KEV catalog. Its EPSS exploit-prediction score is 0% (19th percentile), an estimate of the probability of exploitation in the next 30 days.
What products are affected by CVE-2020-12394?: CVE-2020-12394 affects Mozilla Firefox. See the affected-products list for the exact vulnerable versions.
How do I fix CVE-2020-12394?: Review the linked vendor and NVD advisories for patched versions and mitigations, then upgrade or apply the recommended workaround.
When was CVE-2020-12394 published?: CVE-2020-12394 was published on 2020-05-26 and last updated on 2026-06-17.

References

Affected products (1)

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

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