When loading the shared library that provides the OTR protocol implementation, Thunderbird will initially attempt to open it using a filename that isn't distributed by Thunderbird. If a computer has already been infected with a malicious library of the alternative filename, and the malicious library has been copied to a directory that is contained in the search path for executable libraries, then Thunderbird will load the incorrect library. External Reference: https://www.mozilla.org/en-US/security/advisories/mfsa2021-13/#CVE-2021-29949
Acknowledgments: Name: the Mozilla project Upstream: Tuan Vu Pham
This bug is now closed. Further updates for individual products will be reflected on the CVE page(s): https://access.redhat.com/security/cve/cve-2021-29949