CVE-2026-8973

Memory safety bugs fixed in Thunderbird 151

Published May 19, 2026 CVSS 3.1 · 8.8 High EPSS < 1% KEV · Not listed
Description
Memory safety bugs present in Thunderbird 150. Some of these bugs showed evidence of memory corruption and we presume that with enough effort some of these could have been exploited to run arbitrary code. This vulnerability was fixed in Firefox 151 and Thunderbird 151.

Remediation

No solution or workaround provided in the CVE record

Tracking

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Advisories

No advisories available
History
Type Values Removed Values Added
Description Memory safety bugs present in Firefox 150. Some of these bugs showed evidence of memory corruption and we presume that with enough effort some of these could have been exploited to run arbitrary code. This vulnerability was fixed in Firefox 151 and Thunderbird 151. Memory safety bugs present in Thunderbird 150. Some of these bugs showed evidence of memory corruption and we presume that with enough effort some of these could have been exploited to run arbitrary code. This vulnerability was fixed in Firefox 151 and Thunderbird 151.
Title Memory safety bugs fixed in Firefox 151 Memory safety bugs fixed in Thunderbird 151
Type Values Removed Values Added
Description Memory safety bugs present in Thunderbird 150. Some of these bugs showed evidence of memory corruption and we presume that with enough effort some of these could have been exploited to run arbitrary code. This vulnerability was fixed in Firefox 151 and Thunderbird 151. Memory safety bugs present in Firefox 150. Some of these bugs showed evidence of memory corruption and we presume that with enough effort some of these could have been exploited to run arbitrary code. This vulnerability was fixed in Firefox 151 and Thunderbird 151.
Title Memory safety bugs fixed in Thunderbird 151 Memory safety bugs fixed in Firefox 151
Type Values Removed Values Added
First Time appeared Mozilla thunderbird
CPEs cpe:2.3:a:mozilla:firefox:*:*:*:*:-:*:*:*
cpe:2.3:a:mozilla:thunderbird:*:*:*:*:-:*:*:*
Vendors & Products Mozilla thunderbird
Type Values Removed Values Added
Metrics cvssV3_1

{'score': 9.8, 'vector': 'CVSS:3.1/AV:N/AC:L/PR:N/UI:N/S:U/C:H/I:H/A:H'}

ssvc

{'options': {'Automatable': 'yes', 'Exploitation': 'none', 'Technical Impact': 'total'}, 'version': '2.0.3'}

cvssV3_1

{'score': 8.8, 'vector': 'CVSS:3.1/AV:N/AC:L/PR:N/UI:R/S:U/C:H/I:H/A:H'}

ssvc

{'options': {'Automatable': 'no', 'Exploitation': 'none', 'Technical Impact': 'total'}, 'version': '2.0.3'}

Type Values Removed Values Added
Weaknesses CWE-416
CWE-787
Type Values Removed Values Added
Description Memory safety bugs present in Firefox 150. Some of these bugs showed evidence of memory corruption and we presume that with enough effort some of these could have been exploited to run arbitrary code. This vulnerability was fixed in Firefox 151. Memory safety bugs present in Thunderbird 150. Some of these bugs showed evidence of memory corruption and we presume that with enough effort some of these could have been exploited to run arbitrary code. This vulnerability was fixed in Firefox 151 and Thunderbird 151.
Title Memory safety bugs fixed in Firefox 151 Memory safety bugs fixed in Thunderbird 151
References
Type Values Removed Values Added
Weaknesses CWE-119
Metrics cvssV3_1

{'score': 9.8, 'vector': 'CVSS:3.1/AV:N/AC:L/PR:N/UI:N/S:U/C:H/I:H/A:H'}

ssvc

{'options': {'Automatable': 'yes', 'Exploitation': 'none', 'Technical Impact': 'total'}, 'version': '2.0.3'}

Type Values Removed Values Added
First Time appeared Mozilla
Mozilla firefox
Weaknesses CWE-416
CWE-787
Vendors & Products Mozilla
Mozilla firefox
Weaknesses

Sources

Status
PUBLISHED
Assigner
mozilla
Published
Updated
Oct 21, 2026, 1:50 PM
Reserved
May 19, 2026, 12:30 PM
Status
Modified
Published
May 19, 2026, 2:16 PM
Modified
Oct 21, 2026, 2:17 PM