CVE-2026-49277 Overview
CVE-2026-49277 is a session management vulnerability in Rocket.Chat, an open-source communications platform. The flaw allows deactivated users to retain valid OAuth access. Rocket.Chat fails to revoke OAuth bearer tokens and refresh tokens when an administrator deactivates a user account. A deactivated account can continue using existing access tokens to interact with the platform. The account can also exchange an existing refresh token for a new access token, extending unauthorized access indefinitely. The issue is tracked under [CWE-613: Insufficient Session Expiration] and is fixed in Rocket.Chat versions 8.5.0, 8.4.2, 8.3.4, 8.2.4, 8.1.5, 8.0.6, 7.13.8, and 7.10.12.
Critical Impact
Deactivated accounts retain API access via OAuth tokens, enabling unauthorized data access and actions after administrator-initiated account termination.
Affected Products
- Rocket.Chat versions prior to 8.5.0, 8.4.2, 8.3.4, 8.2.4, 8.1.5, 8.0.6, 7.13.8, and 7.10.12
- Rocket.Chat OAuth authentication subsystem
- Self-hosted and cloud Rocket.Chat deployments using OAuth bearer tokens
Discovery Timeline
- 2026-06-24 - CVE-2026-49277 published to NVD
- 2026-06-25 - Last updated in NVD database
Technical Details for CVE-2026-49277
Vulnerability Analysis
The vulnerability stems from incomplete account lifecycle handling in Rocket.Chat's authentication layer. When an administrator deactivates a user, the platform marks the account as inactive but does not invalidate associated OAuth credentials. Existing bearer tokens remain valid until their natural expiration. Refresh tokens remain usable, allowing a deactivated user to mint new access tokens on demand. This breaks the security expectation that deactivation immediately terminates a principal's access to the system. The issue is classified under [CWE-613] (Insufficient Session Expiration). An attacker who previously obtained OAuth tokens, whether the original account holder or a third party with stolen tokens, can continue calling Rocket.Chat REST and real-time APIs after account deactivation.
Root Cause
The root cause is missing token revocation logic in the user deactivation workflow. The deactivation routine updates the user record but does not iterate through and invalidate the OAuth token store. Refresh tokens, designed to extend session lifetime, become a persistence mechanism rather than a convenience feature. The fix introduces token revocation as part of the deactivation transaction across the listed patched versions.
Attack Vector
Exploitation requires that an attacker already possesses valid OAuth tokens for an account that is later deactivated. The attack vector is network-based via the Rocket.Chat API. After deactivation, the attacker continues to send API requests with the existing bearer token. When the access token expires, the attacker submits the refresh token to the OAuth endpoint and receives a new bearer token. The deactivated user can continue reading messages, accessing channels, and interacting with workspace data depending on the prior permission scope. The vulnerability does not enable privilege escalation. It enables unauthorized continuation of access that should have been terminated.
Detection Methods for CVE-2026-49277
Indicators of Compromise
- API requests authenticated with OAuth bearer tokens belonging to user accounts marked as deactivated in the Rocket.Chat user database
- Successful refresh token grant responses from /api/v1/oauth/token endpoints tied to deactivated principals
- Activity logs showing read or write operations performed by user IDs that no longer have an active status
Detection Strategies
- Correlate Rocket.Chat audit logs with user status changes to identify API activity occurring after a deactivation event
- Monitor OAuth token issuance events and flag refresh grants where the subject account is deactivated
- Review web server and reverse proxy access logs for authenticated requests bearing tokens associated with terminated accounts
Monitoring Recommendations
- Forward Rocket.Chat application and authentication logs to a centralized SIEM for retention and correlation
- Build alerts that join user lifecycle events with authentication and API usage telemetry
- Track OAuth token issuance rates per account and alert on anomalies following administrative actions such as deactivation or role changes
How to Mitigate CVE-2026-49277
Immediate Actions Required
- Upgrade Rocket.Chat to a patched version: 8.5.0, 8.4.2, 8.3.4, 8.2.4, 8.1.5, 8.0.6, 7.13.8, or 7.10.12
- Audit current OAuth token stores and manually revoke tokens belonging to any previously deactivated users
- Review administrative actions over the past retention window to identify deactivations that may have left tokens active
Patch Information
Rocket.Chat addressed the issue by adding token revocation to the user deactivation workflow. The fix is included in releases 8.5.0, 8.4.2, 8.3.4, 8.2.4, 8.1.5, 8.0.6, 7.13.8, and 7.10.12. See the Rocket.Chat GitHub Security Advisory (GHSA-39hg-492f-3c4f) for vendor guidance and full version coverage.
Workarounds
- For deployments that cannot upgrade immediately, manually delete OAuth access and refresh tokens for any deactivated user directly from the database token collection
- Shorten OAuth access and refresh token lifetimes in server configuration to limit the residual access window after deactivation
- Rotate OAuth client secrets and force re-authentication for sensitive integrations following any account deactivation event
Disclaimer: This content was generated using AI. While we strive for accuracy, please verify critical information with official sources.
