Rocket.Chat: Improperly Controlled Modification of Dynamically-Determined Object Attributes
CVE-2026-45687 is a high-severity improperly controlled modification of dynamically-determined object attributes vulnerability in Rocket.Chat from RocketChat, with a CVSS 3.1 base score of 8.5 out of 10. It can be exploited remotely over the network by an attacker with a low-privileged account, without any action from a user. Affected Rocket.Chat versions: >= 8.5.0-rc.0, < 8.5.0; >= 8.4.0-rc.0, < 8.4.1; >= 8.3.0-rc.0, < 8.3.3, and others listed below. The record does not name a fixed version, so check the vendor advisory. There is no confirmed exploitation so far. EPSS estimates a 0.34% chance of exploitation within 30 days, which is low compared with other CVEs.
High severity with no evidence of exploitation so far.
What to do
- Check which version of Rocket.Chat you run against the affected versions below, and install the vendor's latest release.
- Read the advisory on github.com for workarounds and exact fixed builds.
Affected products and versions
| Vendor | Product | Affected versions | Fixed in |
|---|---|---|---|
| RocketChat | Rocket.Chat | >= 8.5.0-rc.0, < 8.5.0; >= 8.4.0-rc.0, < 8.4.1; >= 8.3.0-rc.0, < 8.3.3; >= 8.2.0-rc.0, < 8.2.3; >= 8.1.0-rc.0, < 8.1.4; >= 8.0.0-rc.0, < 8.0.5; >= 7.11.0-rc.0, < 7.13.7; < 7.10.11 | Not stated |
Version data comes from the organisation that assigned the CVE. Confirm against the vendor advisory before deciding you are unaffected.
How the severity score breaks down
- Attack vector
- NetworkCan be exploited remotely over a network, including the internet.
- Attack complexity
- LowNo special conditions are needed; the attack works reliably.
- Privileges required
- LowA basic user account is enough.
- User interaction
- NoneNo action by a victim is required.
- Scope
- ChangedThe attack can reach beyond the vulnerable component into other systems.
- Confidentiality
- HighAll data handled by the component can be read.
- Integrity
- LowLimited modification of data is possible.
- Availability
- NoneAvailability is not affected.
Vector: CVSS:3.1/AV:N/AC:L/PR:L/UI:N/S:C/C:H/I:L/A:N. Scored by CNA (github.com).
Official description
Rocket.Chat is an open-source, secure, fully customizable communications platform. Prior to 8.5.0, 8.4.1, 8.3.3, 8.2.3, 8.1.4, 8.0.5, 7.13.7, and 7.10.11, Rocket.Chat's sendFileMessage DDP method passes the entire attacker-supplied file object into Uploads.updateFileComplete, which merges it directly into a MongoDB $set update via Object.assign. There is no allow-list of writable fields. An attacker can therefore rewrite any column on their own upload record, notably store and the store-specific path fields. This vulnerability is fixed in 8.5.0, 8.4.1, 8.3.3, 8.2.3, 8.1.4, 8.0.5, 7.13.7, and 7.10.11.
Source: the CVE record as published by its numbering authority, via NVD and CVE.org.
The underlying weakness: Improperly Controlled Modification of Dynamically-Determined Object Attributes
The product receives input from an upstream component that specifies multiple attributes, properties, or fields that are to be initialized or updated in an object, but it does not properly control which attributes can be modified.
How developers prevent this class of flaw
- If available, use features of the language or framework that allow specification of allowlists of attributes or fields that are allowed to be modified. If possible, prefer allowlists over denylists. For applications written with Ruby on Rails, use the attr_accessible (allowlist) or attr_protected (denylist) macros in each class that may be used in mass assignment.
- If available, use the signing/sealing features of the programming language to assure that deserialized data has not been tainted. For example, a hash-based message authentication code (HMAC) could be used to ensure that data has not been modified.
- For any externally-influenced input, check the input against an allowlist of internal object attributes or fields that are allowed to be modified.
Timeline
- CVE record published.
- CISA published its SSVC assessment (exploitation: none, automatable: no, technical impact: partial).
- Record last changed materially (score, affected products, status or references).
References
Other vulnerabilities in Rocket.Chat
- 8.1 High severity
- 7.4 High severity
- 9.3 Critical severity
- 9.3 Critical severity
- 9.1 Critical severity
- 9.1 Critical severity
Recent Improperly Controlled Modification of Dynamically-Determined Object Attributes vulnerabilities
- 8.8 High severity
- 8.8 High severity
- 8.8 High severity
- 8.8 High severity
- 8.8 High severity
- 8.8 High severity
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