CVE-2026-65645

Description

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

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EPSS — Exploit Prediction

0.0016

Probability of exploitation

0.05%

Percentile rank

EPSS estimates the probability that this vulnerability will be exploited in the wild within the next 30 days. A higher score means more likely to be exploited.

References

Other References

https://github.com/RocketChat/Rocket.Chat/pull/41814 https://hackerone.com/reports/3852135

Frequently Asked Questions

What is 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

How do I check if I'm vulnerable to CVE-2026-65645? +

You can use Secably's free Website Scanner to check your website for known vulnerabilities. For infrastructure scanning, use the Port Scanner to identify exposed services that may be affected. Check the vendor advisories linked above for specific patch and version information.