CVE-2021-29969

Description

If Thunderbird was configured to use STARTTLS for an IMAP connection, and an attacker injected IMAP server responses prior to the completion of the STARTTLS handshake, then Thunderbird didn't ignore the injected data. This could have resulted in Thunderbird showing incorrect information, for example the attacker could have tricked Thunderbird to show folders that didn't exist on the IMAP server. This vulnerability affects Thunderbird < 78.12.

Category

5.9
CVSS
Severity: Medium
CVSS 3.1 •
CVSS 2.0 •
EPSS 0.15%
Vendor Advisory gentoo.org Vendor Advisory mozilla.org Vendor Advisory mozilla.org
Affected: Mozilla Thunderbird
Published at:
Updated at:

References

Link Tags
https://www.mozilla.org/security/advisories/mfsa2021-30/ vendor advisory
https://bugzilla.mozilla.org/show_bug.cgi?id=1682370 issue tracking permissions required vendor advisory
https://security.gentoo.org/glsa/202208-14 third party advisory vendor advisory

Frequently Asked Questions

What is the severity of CVE-2021-29969?
CVE-2021-29969 has been scored as a medium severity vulnerability.
How to fix CVE-2021-29969?
To fix CVE-2021-29969, 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-2021-29969 being actively exploited in the wild?
As for now, there are no information to confirm that CVE-2021-29969 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-2021-29969?
CVE-2021-29969 affects Mozilla Thunderbird.
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