How severe is CVE-2020-12424?

CVE-2020-12424 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-2020-12424 being actively exploited?

It is not currently listed in CISA's KEV catalog. Its EPSS exploit-prediction score is 1% (69th percentile), an estimate of the probability of exploitation in the next 30 days.

What products are affected by CVE-2020-12424?

CVE-2020-12424 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-2020-12424?

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

When was CVE-2020-12424 published?

CVE-2020-12424 was published on 2020-07-09 and last updated on 2026-06-17.

CVE-2020-12424

CVE-2020-12424 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-276.

Key facts

Severity: Medium (CVSS 3.x base score 6.5)
CVSS v2: 4.3
EPSS exploit prediction: 1% (69th percentile)
Actively exploited: Not listed in CISA KEV
Weakness: CWE-276
Affected product: Mozilla Firefox
Published: 2020-07-09
Last modified: 2026-06-17

Description

When constructing a permission prompt for WebRTC, a URI was supplied from the content process. This URI was untrusted, and could have been the URI of an origin that was previously granted permission; bypassing the prompt. This vulnerability affects Firefox < 78.

Frequently asked questions

What is CVE-2020-12424?: When constructing a permission prompt for WebRTC, a URI was supplied from the content process. This URI was untrusted, and could have been the URI of an origin that was previously granted permission; bypassing the prompt. This vulnerability affects Firefox < 78.
How severe is CVE-2020-12424?: CVE-2020-12424 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-2020-12424 being actively exploited?: It is not currently listed in CISA's KEV catalog. Its EPSS exploit-prediction score is 1% (69th percentile), an estimate of the probability of exploitation in the next 30 days.
What products are affected by CVE-2020-12424?: CVE-2020-12424 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-2020-12424?: Review the linked vendor and NVD advisories for patched versions and mitigations, then upgrade or apply the recommended workaround.
When was CVE-2020-12424 published?: CVE-2020-12424 was published on 2020-07-09 and last updated on 2026-06-17.

References

Affected products (3)

cpe:2.3:a:mozilla:firefox:*:*:*:*:*:*:*:*
cpe:2.3:o:opensuse:leap:15.1:*:*:*:*:*:*:*
cpe:2.3:o:opensuse:leap:15.2:*:*:*:*:*:*:*

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