Related Vulnerabilities: CVE-2021-23968  

A security issue was found in Firefox before version 86.0 and Thunderbird before version 78.8. If Content Security Policy blocked frame navigation, the full destination of a redirect served in the frame was reported in the violation report; as opposed to the original frame URI. This could be used to leak sensitive information contained in such URIs.

Severity High

Remote Yes

Type Information disclosure

Description

A security issue was found in Firefox before version 86.0 and Thunderbird before version 78.8. If Content Security Policy blocked frame navigation, the full destination of a redirect served in the frame was reported in the violation report; as opposed to the original frame URI. This could be used to leak sensitive information contained in such URIs.

AVG-1601 thunderbird 78.7.1-1 High Vulnerable

AVG-1599 firefox 85.0.2-1 86.0-1 High Fixed

https://www.mozilla.org/en-US/security/advisories/mfsa2021-07/#CVE-2021-23968
https://www.mozilla.org/en-US/security/advisories/mfsa2021-09/#CVE-2021-23968
https://bugzilla.mozilla.org/show_bug.cgi?id=1687342