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.
75.0+build3-0ubuntu0.16.04.11:68.7.0+build1-0ubuntu0.16.04.275.0+build3-0ubuntu0.18.04.138.8.0~repack1-0ubuntu138.8.0~repack1-0ubuntu338.8.0~repack1-0ubuntu452.3.1-0ubuntu352.3.1-7fakesync152.8.1-0ubuntu0.18.04.152.9.1-0ubuntu0.18.04.11:68.7.0+build1-0ubuntu0.18.04.175.0+build3-0ubuntu152.9.1-1build152.9.1-1ubuntu368.5.0-1~fakesync68.5.0-2~fakesync68.6.0-168.6.0-1ubuntu11:68.7.0+build1-0ubuntu1Exploitability
AV:NAC:LPR:NUI:NScope
S:UImpact
C:HI:NA:NCVSS:3.1/AV:N/AC:L/PR:N/UI:N/S:U/C:H/I:N/A:N