In "I hate money" before version 4.1.5, an authenticated member of one project can modify and delete members of another project, without knowledge of this other project's private code. This can be further exploited to access all bills of another project without knowledge of this other project's private code. With the default configuration, anybody is allowed to create a new project. An attacker can create a new project and then use it to become authenticated and exploit this flaw. As such, the exposure is similar to an unauthenticated attack, because it is trivial to become authenticated. This is fixed in version 4.1.5.

Affected: PyPI: ihatemoney

### Impact An authenticated member of one project can modify and delete members of another project, without knowledge of this other project's private code. This can be further exploited to access all bills of another project without knowledge of this other project's private code.

With the default configuration, anybody is allowed to create a new project. An attacker can create a new project and then use it to become authenticated and exploit this flaw. As such, the exposure is similar to an unauthenticated attack, because it is trivial to become authenticated.

### Patches ```diff ihatemoney/models.py | 4 ++-- 1 file changed, 2 insertions(+), 2 deletions(-)

diff --git a/ihatemoney/models.py b/ihatemoney/models.py index fe7b519..5691c75 100644 --- a/ihatemoney/models.py +++ b/ihatemoney/models.py @@ -380,7 +380,7 @@ class Person(db.Model): def get_by_name(self, name, project): return ( Person.query.filter(Person.name == name) - .filter(Project.id == project.id) + .filter(Person.project_id == project.id) .one() ) @@ -389,7 +389,7 @@ class Person(db.Model): project = g.project return ( Person.query.filter(Person.id == id) - .filter(Project.id == project.id) + .filter(Person.project_id == project.id) .one() ) ```

### Workarounds

To limit the impact, it is possible to…

Affected: PyPI: ihatemoney

In "I hate money" before version 4.1.5, an authenticated member of one project can modify and delete members of another project, without knowledge of this other project's private code. This can be further exploited to access all bills of another project without knowledge of this other project's private code. With the default configuration, anybody is allowed to create a new project. An attacker can create a new project and then use it to become authenticated and exploit this flaw. As such, the exposure is similar to an unauthenticated attack, because it is trivial to become authenticated. This is fixed in version 4.1.5.