CVE-2020-26970

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.

Category

8.8
CVSS
Severity: High
CVSS 3.1 •
CVSS 2.0 •
EPSS 0.38%
Vendor Advisory mozilla.org Vendor Advisory mozilla.org
Affected: Mozilla Thunderbird
Published at:
Updated at:

References

Link Tags
https://bugzilla.mozilla.org/show_bug.cgi?id=1677338 issue tracking permissions required vendor advisory
https://www.mozilla.org/security/advisories/mfsa2020-53/ vendor advisory

Frequently Asked Questions

What is the severity of CVE-2020-26970?
CVE-2020-26970 has been scored as a high severity vulnerability.
How to fix CVE-2020-26970?
To fix CVE-2020-26970, make sure you are using an up-to-date version of the affected component(s) by checking the vendor release notes. As for now, there are no other specific guidelines available.
Is CVE-2020-26970 being actively exploited in the wild?
As for now, there are no information to confirm that CVE-2020-26970 is being actively exploited. According to its EPSS score, there is a ~0% probability that this vulnerability will be exploited by malicious actors in the next 30 days.
What software or system is affected by CVE-2020-26970?
CVE-2020-26970 affects Mozilla Thunderbird.
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