CVE-2026-93647
criticalAn unauthenticated calendar sender can place active markup in a COUNTER message's RFC From address.
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.
CVSS
9.3
9.3 (CVSS v3.1)
CVSS:3.1/AV:N/AC:L/PR:N/UI:R/S:C/C:H/I:H/A:N Severity source: NVD CVSS v3.1 (cve@rapid7.com)
Timeline (UTC)
Published: 2026-09-25 14:17
Modified: 2026-09-29 21:29
NVD status: Awaiting Analysis
Last synced 2 days ago
Verified against the source API 2026-10-27 06:55 UTC
Exploitation
Not listed in CISA KEV (as of last catalog sync)
Absence from KEV does not mean a CVE is not exploited. Exploitation status: unknown (no authoritative evidence in our sources).
Affected products
Not reported by the source (unknown — not "none").
Weakness classification (CWE)
Source: NVD / CISA. “NVD-CWE-Other” and “NVD-CWE-noinfo” mean NVD could not assign a specific weakness.
Mitigation & advisories
No vendor advisory or patch reference tagged by NVD. Check the references below.
References
- https://wiki.zimbra.com/wiki/Zimbra_Security_Advisories cve@rapid7.com
Data sources
NVD CVE API 2.0 — fetched 2026-10-27 06:55 UTC · record ↗