# CVE-2026-65645: Rocket.Chat Meteor DDP method authorization bypass

Source: https://junglewise.ai/threats/cve-2026-65645-rocket-chat-meteor-ddp-method-authorization-bypass  
Publisher: Junglewise Threat Intelligence, https://junglewise.ai/threats  
Published: 2026-08-21. Updated: 2026-09-25  
License: CC BY 4.0 with a link back

CVE-2026-65645 · Severity: medium · CVSS 4.3 · Published 2026-08-21

Rocket.Chat is a team collaboration platform with messaging and thread features. A flaw in the Meteor DDP protocol methods for retrieving thread lists allows authenticated users without proper authorization to view private threads and messages from rooms they do not have access to, exposing sensitive team communications.

Technologies: [Rocket.Chat](https://junglewise.ai/threats/technologies/rocket-chat). Vendors: [Rocket.Chat](https://junglewise.ai/threats/vendors/rocket-chat).

## Quick answers

**Is CVE-2026-65645 exploited in the wild?** No. Junglewise Threat Intelligence has no report of CVE-2026-65645 being exploited in the wild.

**How severe is CVE-2026-65645?** Medium severity, with a CVSS score of 4.3, published 21 August 2026.

**Which products and versions are affected?** Rocket.Chat before 8.8.0, 8.7.1, 8.6.2, 8.5.3, 8.4.6, 8.3.8, 8.2.8, 8.1.8, and 7.10.15.

**Is there a fix for CVE-2026-65645?** A patch was published on 2026-08-18: Fixes imported in PR #41814 Junglewise finds every place you run it, drafts the upgrade and applies it once you approve.

**How is CVE-2026-65645 attacked?** It is attacked over the network.

**Am I affected by CVE-2026-65645?** Check whether you run Rocket.Chat at an affected version. Junglewise does that check for you around the clock: connect your code, cloud and domains, and it matches new vulnerabilities like this one against what you actually run and tells you when one reaches you.

## Technical details

The vulnerability is an authorization bypass and information disclosure in the Meteor DDP methods getThreadsList and getThreadMessages. These methods accept rid (room ID) and tmid (thread message ID) parameters as raw, untyped inputs with no schema validation, allowing a MongoDB operator object (e.g. {"$gt": "4"}) to be injected in place of a string identifier. The authorization check resolves to a room the attacker already has access to, but the downstream data query fans out across all rooms, disclosing private thread parents and their full reply content. An authenticated attacker with low-privilege access can exploit this via network to retrieve unauthorized thread data. The REST API equivalent (chat.getThreadsList) was patched in v5.0 with AJV type validation, but the DDP methods were never given the same fix.

## Affected products

- Rocket.Chat Rocket.Chat before 8.8.0, 8.7.1, 8.6.2, 8.5.3, 8.4.6, 8.3.8, 8.2.8, 8.1.8, and 7.10.15

## Timeline

- 2026-08-21: disclosed
- 2026-08-18: patched: Fixes imported in PR #41814

## References

- [https://github.com/RocketChat/Rocket.Chat/pull/41814](https://github.com/RocketChat/Rocket.Chat/pull/41814)
- [https://hackerone.com/reports/3852135](https://hackerone.com/reports/3852135)

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