How severe is CVE-2020-12425?

CVE-2020-12425 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 high, integrity none, and availability none.

Is CVE-2020-12425 being actively exploited?

It is not currently listed in CISA's KEV catalog. Its EPSS exploit-prediction score is 1% (68th percentile), an estimate of the probability of exploitation in the next 30 days.

What products are affected by CVE-2020-12425?

CVE-2020-12425 affects Mozilla Firefox. See the affected-products list for the exact vulnerable versions.

How do I fix CVE-2020-12425?

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

When was CVE-2020-12425 published?

CVE-2020-12425 was published on 2020-07-09 and last updated on 2026-06-17.

CVE-2020-12425

CVE-2020-12425 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-125.

Key facts

Severity: Medium (CVSS 3.x base score 6.5)
CVSS v2: 4.3
EPSS exploit prediction: 1% (68th percentile)
Actively exploited: Not listed in CISA KEV
Weakness: CWE-125
Affected product: Mozilla Firefox
Published: 2020-07-09
Last modified: 2026-06-17

Description

Due to confusion processing a hyphen character in Date.parse(), a one-byte out of bounds read could have occurred, leading to potential information disclosure. This vulnerability affects Firefox < 78.

Frequently asked questions

What is CVE-2020-12425?: Due to confusion processing a hyphen character in Date.parse(), a one-byte out of bounds read could have occurred, leading to potential information disclosure. This vulnerability affects Firefox < 78.
How severe is CVE-2020-12425?: CVE-2020-12425 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 high, integrity none, and availability none.
Is CVE-2020-12425 being actively exploited?: It is not currently listed in CISA's KEV catalog. Its EPSS exploit-prediction score is 1% (68th percentile), an estimate of the probability of exploitation in the next 30 days.
What products are affected by CVE-2020-12425?: CVE-2020-12425 affects Mozilla Firefox. See the affected-products list for the exact vulnerable versions.
How do I fix CVE-2020-12425?: Review the linked vendor and NVD advisories for patched versions and mitigations, then upgrade or apply the recommended workaround.
When was CVE-2020-12425 published?: CVE-2020-12425 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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