CVE-2026-93647
CRITICALCVSS 9.3/10
Last modified
CVE-2026-93647 is a critical-severity vulnerability rated 9.3/10 on the CVSS scale. 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..
Description
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.
Metrics
Weakness Enumeration
Affected Software
Source: CNA advisory (CVE.org). NVD analysis pending.
| Vendor | Product | Versions |
|---|---|---|
| Zimbra | Zimbra Collaboration Suite (ZCS) | < 10.1.21 |
References
Timeline
- Published
- Last Modified
- Status
- Received
Frequently Asked Questions
What is 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, allowing the attacker to access mailbox data and act as the victim.
How severe is CVE-2026-93647?
CVE-2026-93647 has a CVSS score of 9.3/10 (CRITICAL severity).
How do I fix CVE-2026-93647?
Check the vendor references and advisories linked above for patched versions and mitigation guidance. You can also run a Strix scan to test if your systems are affected.
How Strix Helps
- How Strix found a critical auth bypass in etcdStrix autonomously discovered a critical authentication bypass in etcd, later designated CVE-2026-33413.
- Autonomous PentestingAI agents that find and validate exploitable vulnerabilities like this one across your applications.
- PR ReviewsPentest every pull request so vulnerable code is caught before it ships to production.
- AI Penetration TestingHow AI-driven penetration testing continuously covers your attack surface.
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Are you affected by CVE-2026-93647?
Run a free Strix scan to check your systems for this vulnerability.
Scan your code nowSource: NVD / NIST