# CVE-2018-6882: Synacor Zimbra Collaboration Suite (ZCS) Cross-Site Scripting (XSS) Vulnerability

Source: https://junglewise.ai/threats/cve-2018-6882-synacor-zimbra-collaboration-suite-zcs-cross-site-scripting-xss  
Publisher: Junglewise Threat Intelligence, https://junglewise.ai/threats  
Published: 2022-04-19. Updated: 2026-05-10  
License: CC BY 4.0 with a link back

CVE-2018-6882 · Severity: critical · CVSS 6.1 · Exploited in the wild · Published 2022-04-19

A cross-site scripting (XSS) vulnerability exists in the ZmMailMsgView.getAttachmentLinkHtml function of Zimbra Collaboration Suite. Remote attackers can inject arbitrary web script or HTML via a malicious Content-Location header in an email attachment.

Technologies: [Synacor Zimbra Collaboration Suite (ZCS)](https://junglewise.ai/threats/technologies/zimbra-collaboration-suite-zcs). Vendors: [Synacor](https://junglewise.ai/threats/vendors/synacor).

## Quick answers

**Is CVE-2018-6882 exploited in the wild?** Yes. CVE-2018-6882 is known to be exploited in the wild, first recorded on 19 April 2022. Treat it as urgent.

**How severe is CVE-2018-6882?** Critical severity, with a CVSS score of 6.1, published 19 April 2022.

**Which products and versions are affected?** Synacor Zimbra Collaboration Suite (ZCS) before 8.7 Patch 1, 8.8.x before 8.8.7.

**Is there a fix for CVE-2018-6882?** 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-2018-6882 attacked?** It is attacked over the network, in a network appliance.

**Am I affected by CVE-2018-6882?** Check whether you run Synacor Zimbra Collaboration Suite (ZCS). 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.

## Affected products

- Synacor Zimbra Collaboration Suite (ZCS) before 8.7 Patch 1, 8.8.x before 8.8.7

## Timeline

- 2018-03-20: disclosed: Initial public disclosure via Securify advisory and mailing lists.
- 2022-04-19: kev added: Added to CISA's Known Exploited Vulnerabilities (KEV) Catalog.

## Related threats

- [Zimbra Collaboration Suite OS command injection in SMTP](https://junglewise.ai/threats/cve-2026-73570-zimbra-collaboration-suite-os-command-injection-in-smtp)
- [Synacor Zimbra Collaboration Suite XSS in Classic UI](https://junglewise.ai/threats/cve-2025-48700-synacor-zimbra-collaboration-suite-xss-in-classic-ui)
- [Synacor Zimbra Collaboration Suite stored XSS in Classic UI](https://junglewise.ai/threats/cve-2025-66376-synacor-zimbra-collaboration-suite-stored-xss-in-classic-ui)
- [Synacor Zimbra Collaboration Suite file inclusion in RestFilter servlet](https://junglewise.ai/threats/cve-2025-68645-synacor-zimbra-collaboration-suite-file-inclusion-in-restfilter)
- [Synacor Zimbra Collaboration Suite XSS in Classic Web Client](https://junglewise.ai/threats/cve-2025-27915-synacor-zimbra-collaboration-suite-xss-in-classic-web-client)