4.3Medium

Rocket.Chat Rocket.Chat

CVE-2026-65645

Rocket.Chat in versions 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, the Meteor DDP methods getThreadsList and getThreadMessages accept rid / tmid as raw, untyped parameters with no schema validation. A MongoDB operator object (e.g. {"$gt": "4"}) can be substituted for a string room-id or message-id. The authorization check resolves to a room the attacker already has access to, while the downstream data query fans out across all rooms - disclosing private thread parents and their full reply content to any low-privilege authenticated user. The REST route chat.getThreadsList was patched in v5.0 (HackerOne report #1446767) by adding rid: {type:'string'} AJV validation. The equivalent DDP method was never given the same fix and remains exploitable

What this means for your business

  • It affects Rocket.Chat. It matters if your company, or a supplier that handles your data, runs it.
  • An attacker can use it remotely, over a network, with an ordinary user login, and without anyone at your company clicking anything.
  • FIRST's prediction model gives it a 0.2% chance of attack attempts being seen in the next 30 days, ranking above 10% of all known flaws.

What to do

  1. 1Check whether your company or your suppliers run Rocket.Chat, and which version. The affected versions are listed further down this page.
  2. 2If you do, apply the vendor's fix. A patch or vendor advisory has been published.

Fastnexa security experts

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Scoring

CVSS
4.3 (v3.1)
Vector
CVSS:3.1/AV:N/AC:L/PR:L/UI:N/S:U/C:L/I:N/A:N
Weakness
CWE-20
Assigned by
support@hackerone.com

Dates

Published
2026-08-21
Last modified
2026-09-04
Sources
NVD

Affected products

  • Rocket.Chat Rocket.Chat- 7.10.15, 8.1.0 - 8.1.8, 8.2.0 - 8.2.8, 8.3.0 - 8.3.8, 8.4.0 - 8.4.6, 8.5.0 - 8.5.3, 8.6.0 - 8.6.2, 8.7.0

As listed in the NVD configuration data. Not a statement about your estate.

References