6.3
Medium
CVE-2026-103500 An attacker could cause a heap buffer overflow by getting a user to open an email that is greater than or equal to 2GB…
Description
An attacker could cause a heap buffer overflow by getting a user to open an email that is greater than or equal to 2GB in size. This vulnerability was fixed in Thunderbird 157, Thunderbird 140.17, and Thunderbird 153.4.
Affected products and versions
| Product | Affected versions | Fixed in |
|---|---|---|
| Thunderbird 157 | earliest → < 157 | 157 |
| Thunderbird 153.4 | earliest → < 153.4 | 153.4 |
| Thunderbird 140.17 | earliest → < 140.17 | 140.17 |
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9.1
Critical