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CVE-2021-23960 Performing garbage collection on re-declared JavaScript variables resulted in a user-after-poison, and a potentially…
Description
Performing garbage collection on re-declared JavaScript variables resulted in a user-after-poison, and a potentially exploitable crash. This vulnerability affects Firefox < 85, Thunderbird < 78.7, and Firefox ESR < 78.7.
Affected products and versions
| Product | Affected versions | Fixed in |
|---|---|---|
| Firefox 85 | earliest → < 85 | 85 |
| Thunderbird 78.7 | earliest → < 78.7 | 78.7 |
| Firefox ESR 78.7 | earliest → < 78.7 | 78.7 |
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