Rocket.Chat: Improper Neutralization of Input During Web Page Generation
CVE-2026-65644 is a high-severity improper neutralization of input during web page generation vulnerability in Rocket.Chat, with a CVSS 3.1 base score of 7.5 out of 10. It can be exploited remotely over the network by an unauthenticated attacker, without any action from a user. The record lists versions 8.8.0, 8.7.1, 8.6.2 as the first without the flaw, so updating Rocket.Chat to one of those releases or later removes the exposure. There is no confirmed exploitation so far. EPSS estimates a 0.48% 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
- Update Rocket.Chat to 8.8.0 or 8.7.1 or 8.6.2 or 8.5.3, whichever matches your release line, or a later version.
- Read the advisory on github.com for workarounds and exact fixed builds.
- Until you can update, restrict network access to the affected service so it is not reachable from untrusted networks.
Affected products and versions
| Vendor | Product | Affected versions | Fixed in |
|---|---|---|---|
| Rocket.Chat | Rocket.Chat | before 8.8.0; before 8.7.1; before 8.6.2; before 8.5.3; before 8.4.6; before 8.3.8; before 8.2.8; before 8.1.8; and 1 more ranges | 8.8.0, 8.7.1, 8.6.2, 8.5.3, 8.4.6, 8.3.8 |
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
- NoneNo account or login is needed.
- User interaction
- NoneNo action by a victim is required.
- Scope
- UnchangedImpact stays within the vulnerable component.
- Confidentiality
- HighAll data handled by the component can be read.
- Integrity
- NoneNothing can be modified.
- Availability
- NoneAvailability is not affected.
Vector: CVSS:3.1/AV:N/AC:L/PR:N/UI:N/S:U/C:H/I:N/A:N. Scored by CISA (ADP).
Official 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 has a REST API endpoint POST /api/v1/livechat/visitor that accepts an unauthenticated, unsanitized name field for Livechat visitors. This name is stored raw and later rendered via dangerouslySetInnerHTML in the Omnichannel Queue side panel (InquireSidePanelItem.tsx), injecting a real, clickable HTML link - pointing to any attacker-controlled domain, with arbitrary social-engineering text - into the DOM of any agent viewing the queue.
Source: the CVE record as published by its numbering authority, via NVD and CVE.org.
The underlying weakness: Improper Neutralization of Input During Web Page Generation
The product does not neutralize or incorrectly neutralizes user-controllable input before it is placed in output that is used as a web page that is served to other users.
How developers prevent this class of flaw
- Use a vetted library or framework that does not allow this weakness to occur or provides constructs that make this weakness easier to avoid. Examples of libraries and frameworks that make it easier to generate properly encoded output include Microsoft's Anti-XSS library, the OWASP ESAPI Encoding module, and Apache Wicket.
- Understand all the potential areas where untrusted inputs can enter your software: parameters or arguments, cookies, anything read from the network, environment variables, reverse DNS lookups, query results, request headers, URL components, e-mail, files, filenames, databases, and any external systems that provide data to the application. Remember that such inputs may be obtained indirectly through API calls.
- For any security checks that are performed on the client side, ensure that these checks are duplicated on the server side, in order to avoid CWE-602. Attackers can bypass the client-side checks by modifying values after the checks have been performed, or by changing the client to remove the client-side checks entirely. Then, these modified values would be submitted to the server.
More Improper Neutralization of Input During Web Page Generation vulnerabilities (CWE-79)
Timeline
- CVE record published.
- CISA published its SSVC assessment (exploitation: none, automatable: yes, technical impact: partial).
- Record last changed materially (score, affected products, status or references).
References
Third-party and government advisories
- hackerone.com/reports/3872858Third Party Advisory, Issue Tracking
Other vulnerabilities in Rocket.Chat
- 7.5 High severity
- 9.8 Critical severity
- 7.5 High severity
- 9.3 Critical severity
- 7.5 High severity
- 9.8 Critical severity
Recent Improper Neutralization of Input During Web Page Generation vulnerabilities
- 8.8 High severity
- 8.7 High severity
- 8.2 High severity
- 8.2 High severity
- 8.0 High severity
- 8.0 High severity
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