CVE-2026-33370
A stored cross-site scripting (XSS) vulnerability exists in the Zimbra Briefcase feature due to insufficient sanitization of specific uploaded file types.
Does this matter?
Lower severity and a low EPSS score (0.21%). Track it; it rarely justifies an emergency change on its own.
Description
An issue was discovered in Zimbra Collaboration (ZCS) 10.0 and 10.1. A stored cross-site scripting (XSS) vulnerability exists in the Zimbra Briefcase feature due to insufficient sanitization of specific uploaded file types. When a user opens a publicly shared Briefcase file containing malicious scripts, the embedded JavaScript executes in the context of the user's session. This allows an attacker to run arbitrary scripts, potentially leading to data exfiltration or other unauthorized actions on behalf of the victim user.
- CVSS 3.1
- 6.1 MEDIUMCVSS:3.1/AV:N/AC:L/PR:N/UI:R/S:C/C:L/I:L/A:N
- EPSS
- 0.21% probability · 11th percentile
- CISA KEV
- Not listed
- Weakness
- CWE-79
- Affected
- synacor/zimbra collaboration suite
- Source
- cve@mitre.org
References
- https://wiki.zimbra.com/wiki/Security_CenterRelease Notes, Vendor Advisory
- https://wiki.zimbra.com/wiki/Zimbra_Releases/10.1.16#Security_FixesRelease Notes
- https://wiki.zimbra.com/wiki/Zimbra_Responsible_Disclosure_PolicyProduct
- https://wiki.zimbra.com/wiki/Zimbra_Security_AdvisoriesVendor Advisory
Source: NVD record, EPSS from FIRST.org, KEV from CISA. Refreshed daily.