Cross-site scripting in Zimbra Collaboration - #VU144523
Published: August 21, 2026
Vulnerability identifier: #VU144523
CSH Severity: Low
CVSS v4: 5.1 [CVSS:4.0/AV:N/AC:L/AT:N/PR:L/UI:P/VC:N/VI:N/VA:N/SC:L/SI:L/SA:N]
CVE-ID: N/A
CWE-ID: CWE-79
Exploitation vector: Remote access
Exploit availability:
No public exploit available
Vulnerability details
The vulnerability allows a remote user to execute arbitrary script in the victim's browser.
The vulnerability exists due to stored cross-site scripting in the Classic Web Client attachment rendering when rendering crafted attachments. A remote user can store crafted attachments to execute arbitrary script in the victim's browser.
User interaction is required to render the malicious content.
Affected software
Zimbra Collaboration
Remediation
Install security update from vendor's website.
Zimbra Collaboration - update to 10.1.20