# CVE-2026-9548: Synology Chat Server XSS in extract domain

Source: https://junglewise.ai/threats/cve-2026-9548-synology-chat-server-xss-in-extract-domain  
Publisher: Junglewise Threat Intelligence, https://junglewise.ai/threats  
Published: 2026-08-28. Updated: 2026-09-25  
License: CC BY 4.0 with a link back

CVE-2026-9548 · Severity: medium · CVSS 6.5 · Published 2026-08-28

Synology Chat Server is a communication platform integrated with Synology's DSM operating system. A cross-site scripting (XSS) vulnerability in the extract domain feature allows authenticated users to inject malicious code via the user interface, potentially enabling them to read or write restricted files and cause limited service disruptions to other users.

Technologies: [Synology Chat Server](https://junglewise.ai/threats/technologies/chat-server). Vendors: [Synology](https://junglewise.ai/threats/vendors/synology).

## Quick answers

**Is CVE-2026-9548 exploited in the wild?** No. Junglewise Threat Intelligence has no report of CVE-2026-9548 being exploited in the wild.

**How severe is CVE-2026-9548?** Medium severity, with a CVSS score of 6.5, published 28 August 2026.

**Which products and versions are affected?** Synology Chat Server before 2.4.5-22148.

**Is there a fix for CVE-2026-9548?** A patch was published on 2026-08-28: Vulnerability details disclosed; patch available in 2.4.5-22148 or above Junglewise finds every place you run it, drafts the upgrade and applies it once you approve.

**How is CVE-2026-9548 attacked?** It is attacked over the network, in a network appliance.

**Am I affected by CVE-2026-9548?** Check whether you run Synology Chat Server 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

This is a reflected or stored XSS vulnerability (CWE-79) in the extract domain component of Synology Chat Server before version 2.4.5-22148. The vulnerability requires authentication and user interaction (UI interaction) to exploit. An attacker with valid credentials can craft a malicious input that executes arbitrary JavaScript in the context of a DSM session, allowing file access and limited denial-of-service actions. A patch is available in version 2.4.5-22148 and above.

## Affected products

- Synology Chat Server before 2.4.5-22148

## Timeline

- 2026-05-26: disclosed: Initial public release of advisory
- 2026-08-28: patched: Vulnerability details disclosed; patch available in 2.4.5-22148 or above

## References

- [https://www.synology.com/en-global/security/advisory/Synology_SA_26_10](https://www.synology.com/en-global/security/advisory/Synology_SA_26_10)

## Related threats

- [Synology Chat Server SSRF in webhook](https://junglewise.ai/threats/cve-2026-9491-synology-chat-server-ssrf-in-webhook)
- [Synology Chat Server cross-site scripting in domain extraction](https://junglewise.ai/threats/cve-2026-40541-synology-chat-server-cross-site-scripting-in-domain-extraction)