What’s Vulnerable › Vulnerabilities

CVE-2026-33368

• Severity: medium (CVSS 6.1 v3.1)
• Exploited in the wild: not listed in CISA KEV
• EPSS: 0.2% probability of exploitation in the next 30 days
• Public exploit or detection template: none known
• Published: 2026-03-20 · updated 2026-06-17
• Weakness: CWE-79

Description

Zimbra Collaboration Suite (ZCS) 10.0 and 10.1 contains a reflected cross-site scripting (XSS) vulnerability in the Classic Webmail REST interface (/h/rest). The application fails to properly sanitize user-supplied input, allowing an unauthenticated attacker to inject malicious JavaScript into a crafted URL. When a victim user accesses the link, the injected script executes in the context of the Zimbra webmail application, which could allow the attacker to perform actions on behalf of the victim.

Affected products

• Zimbra Collaboration: from 10.0.0 before 10.1.16 — fixed in 10.1.16

How to fix

Upgrade to a fixed version: Zimbra Collaboration 10.1.16. Check the vendor advisory for mitigations.

References

• https://wiki.zimbra.com/wiki/Security_Center
• https://wiki.zimbra.com/wiki/Zimbra_Releases/10.1.16#Security_Fixes
• https://wiki.zimbra.com/wiki/Zimbra_Responsible_Disclosure_Policy
• https://wiki.zimbra.com/wiki/Zimbra_Security_Advisories

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