CVE-2026-115474: Zulip: Saving a draft DM to a user bypasses can_access_all_users_group permission
Zulip is an open-source team collaboration tool. From 8.0 until 12.2, in organizations where the Who can view all other users in the organization setting restricted guests from viewing other users, saving or editing a direct message draft did not verify that the sender could access the draft recipients. A guest could thereby gain access to otherwise restricted users' profile information without sending a message. Organizations that did not restrict guest access were unaffected. This issue is fixed in version 12.2.
Remediation
Recommended actions to resolve this vulnerability, in priority order.
- Upgrade
Upgrade
Zulipto a version that resolves this vulnerability.Fixed in 12.2
Event History
Frequently Asked Questions
Which deployments are affected?
Affected deployments run Zulip versions 8.0 through 12.1 and restrict guests from viewing other users through the “Who can view all other users in the organization” setting. Organizations that do not restrict guest access are unaffected.
What access does an attacker need?
An attacker needs a guest account and must be able to save or edit a direct-message draft with restricted users as recipients. They do not need to send the message.
What information could be exposed?
A guest could access profile information for users who should have been hidden from guests. The provided data does not indicate exposure of message contents or modification of user data.
What should be done to remediate the issue?
Upgrade Zulip to version 12.2, which fixes the missing recipient-access verification when saving or editing direct-message drafts.