What is CVE-2020-6827?

When following a link that opened an intent://-schemed URL, causing a custom tab to be opened, Firefox for Android could be tricked into displaying the incorrect URI. *Note: This issue only affects Firefox for Android. Other operating systems are unaffected.*. This vulnerability affects Firefox ESR < 68.7.

How severe is CVE-2020-6827?

CVE-2020-6827 has a CVSS 3.x base score of 4.7, 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-2020-6827 being actively exploited?

It is not currently listed in CISA's KEV catalog. Its EPSS exploit-prediction score is 1% (50th percentile), an estimate of the probability of exploitation in the next 30 days.

What products are affected by CVE-2020-6827?

CVE-2020-6827 affects Mozilla Firefox Esr. See the affected-products list for the exact vulnerable versions.

How do I fix CVE-2020-6827?

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

When was CVE-2020-6827 published?

CVE-2020-6827 was published on 2020-04-24 and last updated on 2026-06-17.

CVE-2020-6827

Q: How severe is CVE-2020-6827?

CVE-2020-6827 has a CVSS 3.x base score of 4.7, 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.

Q: Is CVE-2020-6827 being actively exploited?

It is not currently listed in CISA's KEV catalog. Its EPSS exploit-prediction score is 1% (50th percentile), an estimate of the probability of exploitation in the next 30 days.

Q: What products are affected by CVE-2020-6827?

CVE-2020-6827 affects Mozilla Firefox Esr. See the affected-products list for the exact vulnerable versions.

Q: How do I fix CVE-2020-6827?

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

Q: When was CVE-2020-6827 published?

CVE-2020-6827 was published on 2020-04-24 and last updated on 2026-06-17.

CVE-2020-6827 is a medium-severity vulnerability in Mozilla Firefox Esr with a CVSS 3.x base score of 4.7. 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 4.7)
CVSS v2: 4.3
EPSS exploit prediction: 1% (50th percentile)
Actively exploited: Not listed in CISA KEV
Weakness: CWE-1021
Affected product: Mozilla Firefox Esr
Published: 2020-04-24
Last modified: 2026-06-17

Description

When following a link that opened an intent://-schemed URL, causing a custom tab to be opened, Firefox for Android could be tricked into displaying the incorrect URI. <br> *Note: This issue only affects Firefox for Android. Other operating systems are unaffected.*. This vulnerability affects Firefox ESR < 68.7.

Frequently asked questions

What is CVE-2020-6827?: When following a link that opened an intent://-schemed URL, causing a custom tab to be opened, Firefox for Android could be tricked into displaying the incorrect URI. <br> *Note: This issue only affects Firefox for Android. Other operating systems are unaffected.*. This vulnerability affects Firefox ESR < 68.7.
How severe is CVE-2020-6827?: CVE-2020-6827 has a CVSS 3.x base score of 4.7, 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-2020-6827 being actively exploited?: It is not currently listed in CISA's KEV catalog. Its EPSS exploit-prediction score is 1% (50th percentile), an estimate of the probability of exploitation in the next 30 days.
What products are affected by CVE-2020-6827?: CVE-2020-6827 affects Mozilla Firefox Esr. See the affected-products list for the exact vulnerable versions.
How do I fix CVE-2020-6827?: Review the linked vendor and NVD advisories for patched versions and mitigations, then upgrade or apply the recommended workaround.
When was CVE-2020-6827 published?: CVE-2020-6827 was published on 2020-04-24 and last updated on 2026-06-17.

References

Affected products (1)

cpe:2.3:a:mozilla:firefox_esr:*:*:*:*:*:*:*:*

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