Buffer overflow in Mozilla Firefox
CVE-2026-7323
Memory safety bugs present in Thunderbird ESR 140.10.0 and Thunderbird 150.0.0. 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. T…
Vulnerability class: Buffer Overflow
EPSS: 0.000 (5.8th percentile) — read the EPSS interpretation.
CVSS v3 metric
CVSS v3 base score 7.3 (High). Vector: CVSS:3.1/AV:N/AC:L/PR:N/UI:N/S:U/C:L/I:L/A:L.
Affected products
- Mozilla Firefox — versions 140.10.1, 150.0.1
- Mozilla Thunderbird — versions 140.10.1, 150.0.1
Weakness classification (CWE)
References
- Memory safety bugs fixed in Thunderbird ESR 140.10.1 and Thunderbird 150.0.1 (Broken Link)
- security@mozilla.org (Vendor Advisory)
- security@mozilla.org (Vendor Advisory)
- security@mozilla.org (Vendor Advisory)
- security@mozilla.org (Vendor Advisory)
Frequently asked questions
- What is CVE-2026-7323?
- CVE-2026-7323 is a high-severity vulnerability in Mozilla Firefox, classified under Improper Restriction of Operations within the Bounds of a Memory Buffer. CVSS score: 7.3/10. Published 2026-04-28.
- How severe is CVE-2026-7323?
- High severity. CVSS v3 base score is 7.3 out of 10.