8.8
High
CVE-2023-6858 Firefox was susceptible to a heap buffer overflow in `nsTextFragment` due to insufficient OOM handling
Description
Firefox was susceptible to a heap buffer overflow in `nsTextFragment` due to insufficient OOM handling. This vulnerability affects Firefox ESR < 115.6, Thunderbird < 115.6, and Firefox < 121.
Affected products and versions
| Product | Affected versions | Fixed in |
|---|---|---|
| Firefox ESR 115.6 | earliest → < 115.6 | 115.6 |
| Thunderbird 115.6 | earliest → < 115.6 | 115.6 |
| Firefox 121 | earliest → < 121 | 121 |
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