CVE-2026-6784

  1. OpenCVE
  2. Vulnerabilities (CVE)
  3. CVE-2026-6784
Memory safety bugs present in Firefox 149 and Thunderbird 149. 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 150 and Thunderbird 150.

7.5 /10

CVSS v3 : HIGH

V3 Legend

Vector :

Exploitability : 1.6 / Impact : 5.9

Attack Vector NETWORK

Attack Complexity HIGH

Privileges Required NONE

User Interaction REQUIRED

Confidentiality Impact HIGH

Integrity Impact HIGH

Availability Impact HIGH

Scope UNCHANGED

References
Link Resource
https://bugzilla.mozilla.org/buglist.cgi?bug_id=1536243%2C1745382%2C1851073%2C1893400%2C1963301%2C2001319%2C2002899%2C2012436%2C2014435%2C2016901%2C2019916%2C2020486%2C2020612%2C2020817%2C2021788%2C2022051%2C2022367%2C2022431%2C2023302%2C2023670%2C2024225%2C2024238%2C2024240%2C2024265%2C2024367%2C2024369%2C2024424%2C2024760%2C2025281%2C2025361%2C2025387%2C2025466%2C2025954%2C2025958%2C2026278%2C2026292%2C2026297%2C2026378%2C2027148%2C2027287%2C2027341%2C2027384%2C2027427%2C2027694%2C2027993%2C2028009%2C2028270%2C2028416%2C2028524%2C2029295%2C2029301%2C2029699%2C2029800%2C2029801
https://www.mozilla.org/security/advisories/mfsa2026-30/ Vendor Advisory
https://www.mozilla.org/security/advisories/mfsa2026-33/ Vendor Advisory
Configurations

Configuration 1 (hide)

OR cpe:2.3:a:mozilla:firefox:*:*:*:*:-:*:*:*
cpe:2.3:a:mozilla:thunderbird:*:*:*:*:-:*:*:*
History

29 Apr 2026, 06:16

Type Values Removed Values Added
References
  • {'url': 'https://bugzilla.mozilla.org/buglist.cgi?bug_id=1536243%2C1745382%2C1851073%2C1893400%2C1963301%2C2001319%2C2002899%2C2012436%2C2014435%2C2016901%2C2019916%2C2020486%2C2020612%2C2020817%2C2021788%2C2022051%2C2022367%2C2022431%2C2023302%2C2023670%2C2024225%2C2024238%2C2024240%2C2024265%2C2024367%2C2024369%2C2024424%2C2024760%2C2025281%2C2025361%2C2025387%2C2025466%2C2025954%2C2025958%2C2026278%2C2026292%2C2026297%2C2026378%2C2027148%2C2027287%2C2027341%2C2027384%2C2027427%2C2027694%2C2027993%2C2028009%2C2028270%2C2028416%2C2028524%2C2029295%2C2029301%2C2029461%2C2029699%2C2029800%2C2029801', 'tags': ['Broken Link'], 'source': 'security@mozilla.org'}
  • () https://bugzilla.mozilla.org/buglist.cgi?bug_id=1536243%2C1745382%2C1851073%2C1893400%2C1963301%2C2001319%2C2002899%2C2012436%2C2014435%2C2016901%2C2019916%2C2020486%2C2020612%2C2020817%2C2021788%2C2022051%2C2022367%2C2022431%2C2023302%2C2023670%2C2024225%2C2024238%2C2024240%2C2024265%2C2024367%2C2024369%2C2024424%2C2024760%2C2025281%2C2025361%2C2025387%2C2025466%2C2025954%2C2025958%2C2026278%2C2026292%2C2026297%2C2026378%2C2027148%2C2027287%2C2027341%2C2027384%2C2027427%2C2027694%2C2027993%2C2028009%2C2028270%2C2028416%2C2028524%2C2029295%2C2029301%2C2029699%2C2029800%2C2029801 -

22 Apr 2026, 16:05

Type Values Removed Values Added
References () https://bugzilla.mozilla.org/buglist.cgi?bug_id=1536243%2C1745382%2C1851073%2C1893400%2C1963301%2C2001319%2C2002899%2C2012436%2C2014435%2C2016901%2C2019916%2C2020486%2C2020612%2C2020817%2C2021788%2C2022051%2C2022367%2C2022431%2C2023302%2C2023670%2C2024225%2C2024238%2C2024240%2C2024265%2C2024367%2C2024369%2C2024424%2C2024760%2C2025281%2C2025361%2C2025387%2C2025466%2C2025954%2C2025958%2C2026278%2C2026292%2C2026297%2C2026378%2C2027148%2C2027287%2C2027341%2C2027384%2C2027427%2C2027694%2C2027993%2C2028009%2C2028270%2C2028416%2C2028524%2C2029295%2C2029301%2C2029461%2C2029699%2C2029800%2C2029801 - () https://bugzilla.mozilla.org/buglist.cgi?bug_id=1536243%2C1745382%2C1851073%2C1893400%2C1963301%2C2001319%2C2002899%2C2012436%2C2014435%2C2016901%2C2019916%2C2020486%2C2020612%2C2020817%2C2021788%2C2022051%2C2022367%2C2022431%2C2023302%2C2023670%2C2024225%2C2024238%2C2024240%2C2024265%2C2024367%2C2024369%2C2024424%2C2024760%2C2025281%2C2025361%2C2025387%2C2025466%2C2025954%2C2025958%2C2026278%2C2026292%2C2026297%2C2026378%2C2027148%2C2027287%2C2027341%2C2027384%2C2027427%2C2027694%2C2027993%2C2028009%2C2028270%2C2028416%2C2028524%2C2029295%2C2029301%2C2029461%2C2029699%2C2029800%2C2029801 - Broken Link
References () https://www.mozilla.org/security/advisories/mfsa2026-30/ - () https://www.mozilla.org/security/advisories/mfsa2026-30/ - Vendor Advisory
References () https://www.mozilla.org/security/advisories/mfsa2026-33/ - () https://www.mozilla.org/security/advisories/mfsa2026-33/ - Vendor Advisory
CPE cpe:2.3:a:mozilla:firefox:*:*:*:*:-:*:*:*
cpe:2.3:a:mozilla:thunderbird:*:*:*:*:-:*:*:*
First Time Mozilla
Mozilla firefox
Mozilla thunderbird

22 Apr 2026, 00:16

Type Values Removed Values Added
References
  • () https://www.mozilla.org/security/advisories/mfsa2026-33/ -
Summary (en) Memory safety bugs present in Firefox 149 and Thunderbird 149. 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 150. (en) Memory safety bugs present in Firefox 149 and Thunderbird 149. 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 150 and Thunderbird 150.

21 Apr 2026, 14:16

Type Values Removed Values Added
CVSS v2 : unknown
v3 : unknown 		v2 : unknown
v3 : 7.5
CWE CWE-125
CWE-416
CWE-787

21 Apr 2026, 13:16

Type Values Removed Values Added
New CVE
Information

Published : 2026-04-21 13:16

Updated : 2026-04-29 06:16

NVD link : CVE-2026-6784

Mitre link : CVE-2026-6784

CVE.ORG link : CVE-2026-6784

JSON object : View

Products Affected

mozilla

  • thunderbird
  • firefox
CWE
CWE-125

Out-of-bounds Read

CWE-416

Use After Free

CWE-787

Out-of-bounds Write