CRITICAL 9.3 NVD

CVE-2026-93647

An unauthenticated calendar sender can place active markup in a COUNTER message's RFC From address. Selecting the message in Zimbra Classic triggers stored XSS,

An unauthenticated calendar sender can place active markup in a COUNTER message's RFC From address. Selecting the message in Zimbra Classic triggers stored XSS, allowing the attacker to access mailbox data and act as the victim.

References

https://wiki.zimbra.com/wiki/Zimbra_Security_Advisories

Published: 2026-09-25 · Source: NVD · Feed updated: 2026-09-25

This critical severity vulnerability with a CVSS score of 9.3 was published on 2026-09-25 via NVD.

Risk Timeline

CVE Disclosed2026-09-25 · -1 days ago

Remediation Resources

Official Advisory

wiki.zimbra.com/wiki/Zimbra_Security_Advisories

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