In Redmine before 3.4.11 and 4.0.x before 4.0.4, persistent XSS exists due to textile formatting errors.

The CRM Plugin before 4.2.4 for Redmine allows XSS via crafted vCard data.

Redmine before 3.2.9, 3.3.x before 3.3.6, and 3.4.x before 3.4.4 does not block the --config and --debugger flags to the Mercurial hg program, which allows remote attackers to execute arbitrary commands (through the Mercurial adapter) via vectors involving a branch whose name begins with a --config= or --debugger= substring, a related issue to CVE-2017-17536.

In Redmine before 3.2.7 and 3.3.x before 3.3.4, the reminders function in app/models/mailer.rb does not check whether an issue is visible, which allows remote authenticated users to obtain sensitive information by reading e-mail reminder messages.

Redmine before 3.2.6 and 3.3.x before 3.3.3 mishandles Time Entry rendering in activity views, which allows remote attackers to obtain sensitive information.

In Redmine before 3.2.6 and 3.3.x before 3.3.3, Redmine.pm lacks a check for whether the Repository module is enabled in a project's settings, which might allow remote attackers to obtain sensitive differences information or possibly have unspecified other impact.

In Redmine before 3.2.6 and 3.3.x before 3.3.3, XSS exists because markup is mishandled in wiki content.

In Redmine before 3.2.8, 3.3.x before 3.3.5, and 3.4.x before 3.4.3, XSS exists in app/views/issues/_list.html.erb via crafted column data.

In Redmine before 3.2.8, 3.3.x before 3.3.5, and 3.4.x before 3.4.3, XSS exists in app/helpers/queries_helper.rb via a multi-value field with a crafted value that is mishandled during rendering of an issue list.

In Redmine before 3.2.6 and 3.3.x before 3.3.3, remote attackers can obtain sensitive information (password reset tokens) by reading a Referer log, because account/lost_password does not use a redirect.