CVE-2026-45687: Rocket.Chat mass assignment in sendFileMessage allows data export theft

CVE-2026-45687 · Severity: high · CVSS 8.5 · Published 2026-06-24

A security vulnerability in Rocket.Chat allows any registered user to steal the private data exports of other users. By exploiting a flaw in how the system handles file uploads, an attacker can trick the server into generating a download link for sensitive ZIP files containing another person's message history and account data. This issue specifically affects organizations using cloud storage like Amazon S3 or Google Cloud Storage and can lead to significant unauthorized data exposure.

Technologies: Rocket.Chat. Vendors: Rocket.Chat.

Quick answers

Is CVE-2026-45687 exploited in the wild?
No. Junglewise Threat Intelligence has no report of CVE-2026-45687 being exploited in the wild.
How severe is CVE-2026-45687?
High severity, with a CVSS score of 8.5, published 24 June 2026.
Which products and versions are affected?
Rocket.Chat < 8.5.0, < 8.4.1, < 8.3.3, < 8.2.3, < 8.1.4, < 8.0.5, < 7.13.7, < 7.10.11.
Is there a fix for CVE-2026-45687?
No fixed version is recorded yet. Check the vendor's advisory in the references below. If you run it, Junglewise drafts a mitigation that fits your setup and applies it once you approve, with senior security engineers behind it.
How is CVE-2026-45687 attacked?
It is attacked over the network, in a network appliance.
Am I affected by CVE-2026-45687?
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

A mass assignment vulnerability exists in Rocket.Chat's 'sendFileMessage' DDP method. The method passes an attacker-supplied file object to 'Uploads.updateFileComplete', which uses 'Object.assign' to merge the object into a MongoDB '$set' update without an allow-list. An authenticated attacker can overwrite fields in their own upload record, specifically the 'store' and provider-specific 'path' fields (e.g., 'GoogleStorage.path'). Because Rocket.Chat uses deterministic, predictable paths for user data exports (based on the instance's uniqueID and the victim's userId), an attacker can point their own upload record to a victim's export ZIP. When the attacker then requests their own file, the server generates a signed URL for the victim's data, bypassing authorization checks. This affects instances using Amazon S3, Google Cloud Storage, or WebDAV.

Affected products

  • RocketChat Rocket.Chat < 8.5.0, < 8.4.1, < 8.3.3, < 8.2.3, < 8.1.4, < 8.0.5, < 7.13.7, < 7.10.11

Timeline

  • 2026-05-14: advisory: Vendor advisory published on GitHub
  • 2026-06-24: disclosed: CVE published to NVD

References

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