Improperly Controlled Modification of Dynamically-Determined Object Attributes in Rocket.Chat - CVE-2026-45687

 

Improperly Controlled Modification of Dynamically-Determined Object Attributes in Rocket.Chat - CVE-2026-45687

Published: May 14, 2026


Vulnerability identifier: #VU131421
CSH Severity: Medium
CVSS v4.0: CVSS:4.0/AV:N/AC:L/AT:N/PR:L/UI:N/VC:H/VI:L/VA:N/SC:N/SI:N/SA:N/E:U/U:Green
CVE-ID: CVE-2026-45687
CWE-ID: CWE-915
Exploitation vector: Remote access
Exploit availability: No public exploit available
Vendor: Rocket.Chat Technologies Corp.
Affected software:
Rocket.Chat

Detailed vulnerability description

The vulnerability allows a remote user to disclose sensitive information.

The vulnerability exists due to improperly controlled modification of dynamically-determined object attributes in the sendFileMessage DDP method and upload record handling when processing an attacker-supplied file object. A remote user can modify writable fields such as the storage backend and path on their own upload record to disclose sensitive information.

Exploitation requires an authenticated non-admin account and a cloud-backed upload backend such as Google Cloud Storage or Amazon S3. The victim must have previously generated a data export, and the export path is deterministic from the instance identifier and the victim user ID.


How to mitigate CVE-2026-45687

Install security update from vendor's website.

Sources