Red Hat: CVE-2024-1551: Mozilla: Multipart HTTP Responses would accept the Set-Cookie header in response parts (Multiple Advisories)

Set-Cookie response headers were being incorrectly honored in multipart HTTP responses. If an attacker could control the Content-Type response header, as well as control part of the response body, they could inject Set-Cookie response headers that would have been honored by the browser. This vulnerability affects Firefox < 123, Firefox ESR < 115.8, and Thunderbird < 115.8.