critical9.1
CVE-2026-84639
Triggering an error condition in certain MIME bodies would cause uninitialized memory to be used.
Impact
Triggering an error condition in certain MIME bodies would cause uninitialized memory to be used. This vulnerability was fixed in Thunderbird 155, Thunderbird 140.15, and Thunderbird 153.2.
Affected products
| Vendor | Product | Affected versions |
|---|---|---|
| Mozilla | Thunderbird | before 140.15.0 from 141.0 before 153.2.0 from 154.0 before 155.0 |