VULNERABILITY INTELLIGENCE

CVE-2020-26970

CVSS score8.8 HIGH

EPSS probability1.25%

CISA KEVNot currently listed

Published2020-12-09

Last modified2026-06-17

CVSS vectorCVSS:3.1/AV:N/AC:L/PR:N/UI:R/S:U/C:H/I:H/A:H

Description

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.

Weakness classification

nvd@nist.gov: CWE-787

Primary references

security@mozilla.org — Issue Tracking, Permissions Required, Vendor Advisory
security@mozilla.org — Vendor Advisory
af854a3a-2127-422b-91ae-364da2661108 — Issue Tracking, Permissions Required, Vendor Advisory
af854a3a-2127-422b-91ae-364da2661108 — Vendor Advisory