When handling the filename directive in the Content-Disposition header, the filename would be truncated if the filename contained a NULL character. This could have led to reflected file download attacks potentially tricking users to install malware. This vulnerability affects Firefox < 112, Focus for Android < 112, Firefox ESR < 102.10, Firefox for Android < 112, and Thunderbird < 102.10.
https://www.mozilla.org/security/advisories/mfsa2023-15/
https://www.mozilla.org/security/advisories/mfsa2023-14/