4.3
Medium
CVE-2025-5266 Script elements loading cross-origin resources generated load and error events which leaked information enabling…
Description
Script elements loading cross-origin resources generated load and error events which leaked information enabling XS-Leaks attacks. This vulnerability was fixed in Firefox 139, Firefox ESR 128.11, Thunderbird 139, and Thunderbird 128.11.
Affected products and versions
| Product | Affected versions | Fixed in |
|---|---|---|
| Firefox 139 | earliest → < 139 | 139 |
| Firefox 128.11 | earliest → < 128.11 | 128.11 |
| Firefox ESR 128.11 | earliest → < 128.11 | 128.11 |
| Thunderbird 139 | earliest → < 139 | 139 |
| Thunderbird 128.11 | earliest → < 128.11 | 128.11 |
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