CVE-2020-6821 - CVE House
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Status published High CVE-2020-6821

When reading from areas partially or fully outside the source...

Vulnerability 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.

Impact Analysis

Refer to official advisory for detailed impact metrics.

Remediation

Ensure systems are updated to the latest vendor-supplied patch levels.

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Credits & Attribution

No credits recorded in the NVD database.

References

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Affected Vendor

Affected Software

Thunderbird, Firefox ESR, Firefox
Vulnerable Versions:
unspecified

Timeline

Official Publish: April 24th, 2020
Last Modified: August 4th, 2024
Added to House: July 21st, 2026

CVSS Vectors

V3: CVSS:3.1/AV:N/AC:L/PR:N/UI:N/S:U/C:H/I:N/A:N

Weaknesses (CWE)

No CWE data available

MITRE ATT&CK TTPs

No associated TTPs found for this vulnerability.