CVE-2026-93633 (GCVE-0-2026-93633)
Vulnerability from cvelistv5
Published
2026-10-23 13:25
Modified
2026-10-28 19:51
CWE
  • CWE-79 - Improper neutralization of input during web page generation ('cross-site scripting')
Summary
A CSS sanitization vulnerability in Zimbra Collaboration Suite (ZCS) allows an authenticated user with Briefcase access to publish a document that displays attacker-controlled content under the Zimbra origin. When processing a stylesheet containing non-ASCII characters, DefangFilter appends the final ASCII segment without sanitizing it. HTML stored as application/x-zimbra-doc can therefore retain CSS URL references that the normal sanitizer removes. An attacker can share a crafted document that loads external resources and displays a credential-collection form using Zimbra's own visual assets. Exploitation requires the victim to open the document in a browser that renders the content type inline; credential theft additionally requires form submission. ZCS 10.1.16 and 10.1.20 are affected.
Impacted products
Vendor Product Version
Zimbra Zimbra Collaboration Suite Version: 0   ≤ 10.1.20
Create a notification for this product.
Show details on NVD website


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