CVE-2020-26971

Certain blit values provided by the user were not properly constrained leading to a heap buffer overflow on some video drivers. This vulnerability affects Firefox < 84, Thunderbird < 78.6, and Firefox ESR < 78.6.

• CWE-787

• https://bugzilla.mozilla.org/show_bug.cgi?id=1663466Permissions Required, Vendor Advisory
• https://www.mozilla.org/security/advisories/mfsa2020-54/Vendor Advisory
• https://www.mozilla.org/security/advisories/mfsa2020-55/Vendor Advisory
• https://www.mozilla.org/security/advisories/mfsa2020-56/Vendor Advisory
• https://bugzilla.mozilla.org/show_bug.cgi?id=1663466Permissions Required, Vendor Advisory
• https://www.mozilla.org/security/advisories/mfsa2020-54/Vendor Advisory
• https://www.mozilla.org/security/advisories/mfsa2020-55/Vendor Advisory
• https://www.mozilla.org/security/advisories/mfsa2020-56/Vendor Advisory

Published

Jan 7, 2021

Last Modified

Jun 17, 2026

Status

Modified

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