fix: resolve group permission conflicts with multiple groups (#6017)

* fix: resolve group permission conflicts with multiple groups

When a user belonged to multiple groups with different permissions for the
same collection, only the permissions from one group were applied instead
of combining them properly. This caused users to see incorrect access levels
when initially viewing collection items.

The fix combines permissions from all user groups by taking the most
permissive settings:
- read_only: false if ANY group allows write access
- hide_passwords: false if ANY group allows password viewing
- manage: true if ANY group allows management

This ensures users immediately see the correct permissions when opening
collection entries, matching the behavior after editing and saving.

* Update src/api/core/ciphers.rs

Co-authored-by: Mathijs van Veluw <black.dex@gmail.com>

* fix: format

* fix: restrict collection manage permissions to managers only

Prevent users from getting logged out when they have manage permissions by only allowing manage permissions for MembershipType::Manager and higher roles.

* refactor: cipher permission logic to prioritize user access

Updated permission checks to return user collection permissions if available, otherwise fallback to group permissions. Clarified comments to indicate user permissions overrule group permissions and corrected the logic for the 'manage' flag to use boolean OR instead of AND.

---------

Co-authored-by: Mathijs van Veluw <black.dex@gmail.com>

.github/ISSUE_TEMPLATE/bug_report.yml

@@ -20,17 +20,17 @@ body:
         See here [how to enable the admin page](https://github.com/dani-garcia/vaultwarden/wiki/Enabling-admin-page).
 
         > [!IMPORTANT]
-        > :bangbang: Search for existing **Open _AND_ Closed** [Issues](https://github.com/dani-garcia/vaultwarden/issues?q=is%3Aissue%20) **_AND_** [Discussions](https://github.com/dani-garcia/vaultwarden/discussions?discussions_q=) regarding your topic before posting!
+        > ## :bangbang: Search for existing **Closed _AND_ Open** [Issues](https://github.com/dani-garcia/vaultwarden/issues?q=is%3Aissue%20) **_AND_** [Discussions](https://github.com/dani-garcia/vaultwarden/discussions?discussions_q=) regarding your topic before posting! :bangbang:
   #
   - type: checkboxes
     id: checklist
     attributes:
       label: Prerequisites
-      description: Please confirm you have completed the following before submitting an issue
+      description: Please confirm you have completed the following before submitting an issue!
       options:
-        - label: I have searched the existing issues and discussions
+        - label: I have searched the existing **Closed _AND_ Open** [Issues](https://github.com/dani-garcia/vaultwarden/issues?q=is%3Aissue%20) **_AND_** [Discussions](https://github.com/dani-garcia/vaultwarden/discussions?discussions_q=)
           required: true
-        - label: I have read the documentation
+        - label: I have searched and read the [documentation](https://github.com/dani-garcia/vaultwarden/wiki/)
           required: true
   #
   - id: support-string

src/api/core/ciphers.rs

@@ -1924,11 +1924,21 @@ impl CipherSyncData {
 
         // Generate a HashMap with the collections_uuid as key and the CollectionGroup record
         let user_collections_groups: HashMap<CollectionId, CollectionGroup> = if CONFIG.org_groups_enabled() {
-            CollectionGroup::find_by_user(user_id, conn)
-                .await
-                .into_iter()
-                .map(|collection_group| (collection_group.collections_uuid.clone(), collection_group))
-                .collect()
+            CollectionGroup::find_by_user(user_id, conn).await.into_iter().fold(
+                HashMap::new(),
+                |mut combined_permissions, cg| {
+                    combined_permissions
+                        .entry(cg.collections_uuid.clone())
+                        .and_modify(|existing| {
+                            // Combine permissions: take the most permissive settings.
+                            existing.read_only &= cg.read_only; // false if ANY group allows write
+                            existing.hide_passwords &= cg.hide_passwords; // false if ANY group allows password view
+                            existing.manage |= cg.manage; // true if ANY group allows manage
+                        })
+                        .or_insert(cg);
+                    combined_permissions
+                },
+            )
         } else {
             HashMap::new()
         };

src/db/models/cipher.rs

@@ -612,19 +612,20 @@ impl Cipher {
                     // User permissions
                     if let Some(cu) = cipher_sync_data.user_collections.get(collection) {
                         rows.push((cu.read_only, cu.hide_passwords, cu.manage));
-                    }
-
                     // Group permissions
-                    if let Some(cg) = cipher_sync_data.user_collections_groups.get(collection) {
+                    } else if let Some(cg) = cipher_sync_data.user_collections_groups.get(collection) {
                         rows.push((cg.read_only, cg.hide_passwords, cg.manage));
                     }
                 }
             }
             rows
         } else {
-            let mut access_flags = self.get_user_collections_access_flags(user_uuid, conn).await;
-            access_flags.append(&mut self.get_group_collections_access_flags(user_uuid, conn).await);
-            access_flags
+            let user_permissions = self.get_user_collections_access_flags(user_uuid, conn).await;
+            if !user_permissions.is_empty() {
+                user_permissions
+            } else {
+                self.get_group_collections_access_flags(user_uuid, conn).await
+            }
         };
 
         if rows.is_empty() {
@@ -633,6 +634,9 @@ impl Cipher {
         }
 
         // A cipher can be in multiple collections with inconsistent access flags.
+        // Also, user permission overrule group permissions
+        // and only user permissions are returned by the code above.
+        //
         // For example, a cipher could be in one collection where the user has
         // read-only access, but also in another collection where the user has
         // read/write access. For a flag to be in effect for a cipher, upstream
@@ -641,13 +645,15 @@ impl Cipher {
         // and `hide_passwords` columns. This could ideally be done as part of the
         // query, but Diesel doesn't support a min() or bool_and() function on
         // booleans and this behavior isn't portable anyway.
+        //
+        // The only exception is for the `manage` flag, that needs a boolean OR!
         let mut read_only = true;
         let mut hide_passwords = true;
         let mut manage = false;
         for (ro, hp, mn) in rows.iter() {
             read_only &= ro;
             hide_passwords &= hp;
-            manage &= mn;
+            manage |= mn;
         }
 
         Some((read_only, hide_passwords, manage))

src/db/models/collection.rs

@@ -97,13 +97,13 @@ impl Collection {
                         (
                             cu.read_only,
                             cu.hide_passwords,
-                            cu.manage || (is_manager && !cu.read_only && !cu.hide_passwords),
+                            is_manager && (cu.manage || (!cu.read_only && !cu.hide_passwords)),
                         )
                     } else if let Some(cg) = cipher_sync_data.user_collections_groups.get(&self.uuid) {
                         (
                             cg.read_only,
                             cg.hide_passwords,
-                            cg.manage || (is_manager && !cg.read_only && !cg.hide_passwords),
+                            is_manager && (cg.manage || (!cg.read_only && !cg.hide_passwords)),
                         )
                     } else {
                         (false, false, false)
@@ -114,7 +114,9 @@ impl Collection {
         } else {
             match Membership::find_confirmed_by_user_and_org(user_uuid, &self.org_uuid, conn).await {
                 Some(m) if m.has_full_access() => (false, false, m.atype >= MembershipType::Manager),
-                Some(_) if self.is_manageable_by_user(user_uuid, conn).await => (false, false, true),
+                Some(m) if m.atype == MembershipType::Manager && self.is_manageable_by_user(user_uuid, conn).await => {
+                    (false, false, true)
+                }
                 Some(m) => {
                     let is_manager = m.atype == MembershipType::Manager;
                     let read_only = !self.is_writable_by_user(user_uuid, conn).await;