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CVE-2020-26959 During browser shutdown, reference decrementing could have occured on a previously freed object, resulting in a…
Description
During browser shutdown, reference decrementing could have occured on a previously freed object, resulting in a use-after-free, memory corruption, and a potentially exploitable crash. This vulnerability affects Firefox < 83, Firefox ESR < 78.5, and Thunderbird < 78.5.
Affected products and versions
| Product | Affected versions | Fixed in |
|---|---|---|
| Firefox 83 | earliest → < 83 | 83 |
| Firefox ESR 78.5 | earliest → < 78.5 | 78.5 |
| Thunderbird 78.5 | earliest → < 78.5 | 78.5 |
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