CVE-2020-6821

Description

When reading from areas partially or fully outside the source resource with WebGL's <code>copyTexSubImage</code> method, the specification requires the returned values be zero. Previously, this memory was uninitialized, leading to potentially sensitive data disclosure. This vulnerability affects Thunderbird < 68.7.0, Firefox ESR < 68.7, and Firefox < 75.

Category

7.5
CVSS
Severity: High
CVSS 3.1 •
CVSS 2.0 •
EPSS 0.54%
Vendor Advisory ubuntu.com Vendor Advisory mozilla.org Vendor Advisory mozilla.org Vendor Advisory mozilla.org
Affected: Mozilla Thunderbird
Affected: Mozilla Firefox ESR
Affected: Mozilla Firefox
Published at:
Updated at:

References

Link Tags
https://www.mozilla.org/security/advisories/mfsa2020-13/ vendor advisory
https://www.mozilla.org/security/advisories/mfsa2020-12/ vendor advisory
https://www.mozilla.org/security/advisories/mfsa2020-14/ vendor advisory
https://bugzilla.mozilla.org/show_bug.cgi?id=1625404 issue tracking permissions required
https://usn.ubuntu.com/4335-1/ third party advisory vendor advisory

Frequently Asked Questions

What is the severity of CVE-2020-6821?
CVE-2020-6821 has been scored as a high severity vulnerability.
How to fix CVE-2020-6821?
To fix CVE-2020-6821, make sure you are using an up-to-date version of the affected component(s) by checking the vendor release notes. As for now, there are no other specific guidelines available.
Is CVE-2020-6821 being actively exploited in the wild?
As for now, there are no information to confirm that CVE-2020-6821 is being actively exploited. According to its EPSS score, there is a ~1% probability that this vulnerability will be exploited by malicious actors in the next 30 days.
What software or system is affected by CVE-2020-6821?
CVE-2020-6821 affects Mozilla Thunderbird, Mozilla Firefox ESR, Mozilla Firefox.
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