4.0
Medium
CVE-2025-0239 When using Alt-Svc, ALPN did not properly validate certificates when the original server is redirecting to an insecure…
Description
When using Alt-Svc, ALPN did not properly validate certificates when the original server is redirecting to an insecure site. This vulnerability was fixed in Firefox 134, Firefox ESR 128.6, Thunderbird 134, and Thunderbird 128.6.
Affected products and versions
| Product | Affected versions | Fixed in |
|---|---|---|
| Firefox 134 | earliest → < 134 | 134 |
| Firefox 128.6 | earliest → < 128.6 | 128.6 |
| Firefox ESR 128.6 | earliest → < 128.6 | 128.6 |
| Thunderbird 134 | earliest → < 134 | 134 |
| Thunderbird 128.6 | earliest → < 128.6 | 128.6 |
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