Basecamp: Spam & Clearance checks disabled with existing referenced Message-ID

A vulnerability in the inbound email processing allowed crafted emails to bypass spam filtering and The Screener when they appeared to be in reply to an existing thread...

CVE-2023-1777 Information disclosure in linked message previews

Mattermost allows an attacker to request a preview of an existing message when creating a new message via the createPost API call, disclosing the contents of the linked message...