CVE-2026-84144 Internally found bugs fixed in Thunderbird 155 and Thunderbird ESR 153.2

Internally found bugs present in Thunderbird 154 and Thunderbird ESR 153.1. Some of these bugs showed evidence of memory corruption or another security-relevant defect and we presume that with enough effort some of these could have been exploited. This vulnerability was fixed in Firefox 155,...

CVE-2026-84143

CVE-2026-84143 covers internally found bugs in Thunderbird 154 , Thunderbird ESR 153.1 , and Thunderbird ESR 140.14 , some showing evidence of memory corruption or other security-relevant defects. Mozilla presumes some could have been exploited with enough effort, but no confirmed in-the-wild exp...

CVE-2026-84143 Internally found bugs fixed in Thunderbird 155, Thunderbird ESR 153.2 and Thunderbird ESR 140.15

Internally found bugs present in Thunderbird 154, Thunderbird ESR 153.1 and Thunderbird ESR 140.14. Some of these bugs showed evidence of memory corruption or another security-relevant defect and we presume that with enough effort some of these could have been exploited. This vulnerability was...

EUVD-2026-69091

Internally found bugs present in Thunderbird 154, Thunderbird ESR 153.1 and Thunderbird ESR 140.14. Some of these bugs showed evidence of memory corruption or another security-relevant defect and we presume that with enough effort some of these could have been exploited. This vulnerability was...

CVE-2026-84142 Internally found bugs fixed in Thunderbird 155

Internally found bugs present in Thunderbird 154. Some of these bugs showed evidence of memory corruption or another security-relevant defect and we presume that with enough effort some of these could have been exploited. This vulnerability was fixed in Firefox 155 and Thunderbird 155...

CVE-2026-84142

Internally found bugs present in Thunderbird 154. Some of these bugs showed evidence of memory corruption or another security-relevant defect and we presume that with enough effort some of these could have been exploited. This vulnerability was fixed in Firefox 155 and Thunderbird 155...

EUVD-2026-69090

Internally found bugs present in Thunderbird 154. Some of these bugs showed evidence of memory corruption or another security-relevant defect and we presume that with enough effort some of these could have been exploited. This vulnerability was fixed in Firefox 155 and Thunderbird 155...

CVE-2026-84142

Internally found bugs present in Thunderbird 154. Some of these bugs showed evidence of memory corruption or another security-relevant defect and we presume that with enough effort some of these could have been exploited. This vulnerability was fixed in Firefox 155 and Thunderbird 155...

CVE-2026-84140 Site isolation issue in the DOM: Navigation component

Site isolation issue in the DOM: Navigation component. This vulnerability was fixed in Firefox 155, Firefox ESR 153.2, Thunderbird 155, and Thunderbird 153.2...

EUVD-2026-69080

Information disclosure in the Networking: HTTP component. This vulnerability was fixed in Firefox 155, Firefox ESR 153.2, Thunderbird 155, and Thunderbird 153.2...

CVE-2026-84145

Internally discovered bugs in Firefox 154 , Firefox ESR 153.1 , Firefox ESR 140.14 , and Firefox ESR 115.39 included defects showing evidence of memory corruption or other security-relevant issues. Mozilla noted that with enough effort some of these bugs could potentially have been exploited, tho...

EUVD-2026-69068

Internally found bugs present in Thunderbird 154, Thunderbird ESR 153.1 and Thunderbird ESR 140.14. Some of these bugs showed evidence of memory corruption or another security-relevant defect and we presume that with enough effort some of these could have been exploited. This vulnerability was...

CVE-2026-84145

Internally found bugs present in Thunderbird 154, Thunderbird ESR 153.1 and Thunderbird ESR 140.14. Some of these bugs showed evidence of memory corruption or another security-relevant defect and we presume that with enough effort some of these could have been exploited. This vulnerability was...

CVE-2026-84145 Internally found bugs fixed in Thunderbird 155, Thunderbird ESR 153.2 and Thunderbird ESR 140.15

Internally found bugs present in Thunderbird 154, Thunderbird ESR 153.1 and Thunderbird ESR 140.14. Some of these bugs showed evidence of memory corruption or another security-relevant defect and we presume that with enough effort some of these could have been exploited. This vulnerability was...

CVE-2026-84145 Internally found bugs fixed in Thunderbird 155, Thunderbird ESR 153.2 and Thunderbird ESR 140.15

Internally found bugs present in Thunderbird 154, Thunderbird ESR 153.1 and Thunderbird ESR 140.14. Some of these bugs showed evidence of memory corruption or another security-relevant defect and we presume that with enough effort some of these could have been exploited. This vulnerability was...

EUVD-2026-69066

Sandbox escape due to use-after-free in the DOM: Security component. This vulnerability was fixed in Firefox 155, Firefox ESR 115.40, Firefox ESR 140.15, Firefox ESR 153.2, Thunderbird 155, Thunderbird 140.15, and Thunderbird 153.2...

CVE-2026-84121

Sandbox escape due to use-after-free in the DOM: Security component. This vulnerability was fixed in Firefox 155, Firefox ESR 115.40, Firefox ESR 140.15, Firefox ESR 153.2, Thunderbird 155, Thunderbird 140.15, and Thunderbird 153.2...

CVE-2026-84121 Sandbox escape due to use-after-free in the DOM: Security component

Sandbox escape due to use-after-free in the DOM: Security component. This vulnerability was fixed in Firefox 155, Firefox ESR 115.40, Firefox ESR 140.15, Firefox ESR 153.2, Thunderbird 155, Thunderbird 140.15, and Thunderbird 153.2...

CVE-2026-84121 Sandbox escape due to use-after-free in the DOM: Security component

Sandbox escape due to use-after-free in the DOM: Security component. This vulnerability was fixed in Firefox 155, Firefox ESR 115.40, Firefox ESR 140.15, Firefox ESR 153.2, Thunderbird 155, Thunderbird 140.15, and Thunderbird 153.2...

CVE-2026-84121

CVE-2026-84121 is a sandbox escape in Mozilla Firefox caused by a use-after-free in the DOM: Security component. A successful exploit allows an attacker to escape the browser sandbox, resulting in total technical impact (high confidentiality, integrity, and availability impact) across a changed s...