CVE-2021-29956

OpenPGP secret keys that were imported using Thunderbird version 78.8.1 up to version 78.10.1 were stored unencrypted on the users local disk. The master password protection was inactive for those keys. Version 78.10.2 will restore the protection mechanism for newly imported keys, and will automatically protect keys that had been imported using affected Thunderbird versions. This vulnerability affects Thunderbird < 78.10.2.

Weakness

The product stores sensitive information in cleartext within a resource that might be accessible to another control sphere.

Affected Software

Extended Description

Because the information is stored in cleartext (i.e., unencrypted), attackers could potentially read it. Even if the information is encoded in a way that is not human-readable, certain techniques could determine which encoding is being used, then decode the information. When organizations adopt cloud services, it can be easier for attackers to access the data from anywhere on the Internet. In some systems/environments such as cloud, the use of “double encryption” (at both the software and hardware layer) might be required, and the developer might be solely responsible for both layers, instead of shared responsibility with the administrator of the broader system/environment.

Potential Mitigations

Related Attack Patterns

• https://cwe.mitre.org/data/definitions/37.html

References

• https://bugzilla.mozilla.org/show_bug.cgi?id=1710290
• https://www.mozilla.org/security/advisories/mfsa2021-22/