An issue was discovered in Zimbra Collaboration (ZCS) 10.0 and 10.1. A cross-site request forgery (CSRF) vulnerability exists in Zimbra Webmail due to improper validation of CSRF tokens. The application accepts CSRF tokens supplied within the request body instead of requiring them through the expected request header. An attacker can exploit this issue by tricking an authenticated user into submitting a crafted request. This may allow unauthorized actions to be performed on behalf of the victim.
Conclusion & alert: CVE-2026-33372 is rated Low Risk (23/100): CVSS Medium severity, with low exploitation likelihood (EPSS 0.02%). Mandatory action: Monitor for updates and reassess as exploit intelligence or EPSS changes.
Risk is dynamic; we continuously reassess and refresh what is shown on this page as upstream context changes.
EPSS lead: Daily EPSS estimates relative likelihood of exploitation; percentile ranks this CVE among scored vulnerabilities (higher = more severe relative rank).
| # | Date | Old EPSS score | New EPSS score | Delta (New - Old) |
|---|---|---|---|---|
| 1 | 2026-03-21 | — | 0.02% | — |
Full EPSS history (1 record total)
CVSS metrics for this CVE.
| Base score | Version | Severity | Vector | Exploitability | Impact | Score source |
|---|---|---|---|---|---|---|
| 5.4 | 3.1 | MEDIUM |
|
2.8 | 2.5 | 134c704f-9b21-4f2e-91b3-4a467353bcc0 |
| Vendor | Product | Version | Raw CPE |
|---|---|---|---|
| synacor | zimbra_collaboration_suite | >= 10.0.0, < 10.1.16 | cpe:2.3:a:synacor:zimbra_collaboration_suite:*:*:*:*:*:*:*:* |
| URL | Tags |
|---|---|
| https://wiki.zimbra.com/wiki/Security_Center | Vendor Advisory Release Notes |
| https://wiki.zimbra.com/wiki/Zimbra_Releases/10.1.16#Security_Fixes | Release Notes |
| https://wiki.zimbra.com/wiki/Zimbra_Responsible_Disclosure_Policy | Product |
| https://wiki.zimbra.com/wiki/Zimbra_Security_Advisories | Vendor Advisory |