Buffer overflow in Mozilla Thunderbird

CVE-2020-26970

When reading SMTP server status codes, Thunderbird writes an integer value to a position on the stack that is intended to contain just one byte. Depending on processor architecture and stack layout, this leads to stack corruption that may be exploitable. This vulnerability affects Thunderbird < 78.5.1.

Vulnerability class: Buffer Overflow

EPSS: 0.012 (65.6th percentile) — read the EPSS interpretation.

CVSS v3 metric

CVSS v3 base score 8.8 (High). Vector: CVSS:3.1/AV:N/AC:L/PR:N/UI:R/S:U/C:H/I:H/A:H.

Affected products

Weakness classification (CWE)

References

Frequently asked questions

What is CVE-2020-26970?
CVE-2020-26970 is a high-severity vulnerability in Mozilla Thunderbird, classified under Out-of-bounds Write. CVSS score: 8.8/10. Published 2020-12-09.
How severe is CVE-2020-26970?
High severity. CVSS v3 base score is 8.8 out of 10.