CVE-2020-26970
Mozilla: Stack overflow due to incorrect parsing of SMTP server response codes
Severity
ImportantRed Hat Product Security
CVSS 3.1
Review impact separately from score.
Published · December 1, 2020
Updated · November 22, 2025
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.
CVSS score applicability
The CVSS score(s) listed for this vulnerability do not reflect the associated product's status, and are included for informational purposes to better understand the severity of this vulnerability.
Mitigation
No mitigation is specified in collected source.
CVSS / CWE
CVSS 3.1 · 8.8CVSS:3.1/AV:N/AC:L/PR:N/UI:R/S:U/C:H/I:H/A:H
CWE-121 · Stack-based Buffer Overflow