CVE-2026-93633
mediumpriority · track · 0EPSS 0.002 · 7 %ileEPSS · scored 2026-10-27
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.
cvss
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base score 0–10 · higher = more severe · hover a vector to decode
weaknesses
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affected products
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No affected products recorded.
sources
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references (2) nvd
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