CVE-2020-26970

high
Published — · Modified —
CVSS v3
CVSS v2
VIR risk
8.0

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.

Predictions

Exploit likelihood
20%
Patch ETA

Heuristic predictions, AS-IS, for prioritization only.

Mitigations

vendor Authored 2026-05-27

Vendor advisory: debian — https://security-tracker.debian.org/tracker/CVE-2020-26970

vendor Authored 2026-05-27

Vendor advisory: arch — https://security.archlinux.org/ASA-202012-23

OS impact

OSVersionStatusFixed in
arch archfixed78.6.0-1
debian debianbookwormfixed1:78.5.1-1
debian debianbullseyefixed1:78.5.1-1
debian debianforkyfixed1:78.5.1-1
debian debiansidfixed1:78.5.1-1
debian debiantrixiefixed1:78.5.1-1

References

Verify integrity in audit chain (admin only). AS-IS.