Description
An issue was discovered in ProxyServlet.java in the /proxy servlet in Zimbra Collaboration Suite 8.8 before 8.8.15 Patch 23 and 9.x before 9.0.0 Patch 16. The value of the X-Host header overwrites the value of the Host header in proxied requests. The value of X-Host header is not checked against the whitelist of hosts Zimbra is allowed to proxy to (the zimbraProxyAllowedDomains setting).
Metrics
CVSS 3.1 9.8/10
CVSS:3.1/AV:N/AC:L/PR:N/UI:N/S:U/C:H/I:H/A:HWeakness enumeration
Affected software
| Vendor | Product | Versions |
|---|---|---|
| n/a | n/a | n/a |
References
- https://blog.sonarsource.com/zimbra-webmail-compromise-via-emailExploit, Third Party Advisory
- https://wiki.zimbra.com/wiki/Security_CenterRelease Notes, Vendor Advisory
- https://wiki.zimbra.com/wiki/Zimbra_Releases/8.8.15/P23Release Notes, Vendor Advisory
- https://wiki.zimbra.com/wiki/Zimbra_Releases/9.0.0/P16Release Notes, Vendor Advisory
- https://wiki.zimbra.com/wiki/Zimbra_Security_AdvisoriesVendor Advisory
- https://blog.sonarsource.com/zimbra-webmail-compromise-via-emailExploit, Third Party Advisory
- https://wiki.zimbra.com/wiki/Security_CenterRelease Notes, Vendor Advisory
- https://wiki.zimbra.com/wiki/Zimbra_Releases/8.8.15/P23Release Notes, Vendor Advisory
- https://wiki.zimbra.com/wiki/Zimbra_Releases/9.0.0/P16Release Notes, Vendor Advisory
- https://wiki.zimbra.com/wiki/Zimbra_Security_AdvisoriesVendor Advisory
Timeline
- Published
- Jul 2, 2021
- Last modified
- Jun 17, 2026
- NVD status
- Modified