CVE-2021-35207

Severity: medium (CVSS 6.1 v3.1)
Exploited in the wild: not listed in CISA KEV
EPSS: 3.3% probability of exploitation in the next 30 days
Public exploit or detection template: none known
Published: 2021-07-02 · updated 2026-06-17
Weakness: CWE-79

Description

An issue was discovered in Zimbra Collaboration Suite 8.8 before 8.8.15 Patch 23 and 9.0 before 9.0.0 Patch 16. An XSS vulnerability exists in the login component of Zimbra Web Client, in which an attacker can execute arbitrary JavaScript by adding executable JavaScript to the loginErrorCode parameter of the login url.

Affected products

Zimbra Collaboration: from 8.8 before 8.8.15; 8.8.15, 8.8.15-p1, 8.8.15-p10, 8.8.15-p11, 8.8.15-p12, 8.8.15-p13 (+33) — fixed in 8.8.15

How to fix

Upgrade to a fixed version: Zimbra Collaboration 8.8.15. Check the vendor advisory for mitigations.

References

https://wiki.zimbra.com/wiki/Security_Center
https://wiki.zimbra.com/wiki/Zimbra_Releases/8.8.15/P23
https://wiki.zimbra.com/wiki/Zimbra_Releases/9.0.0/P16
https://wiki.zimbra.com/wiki/Zimbra_Security_Advisories
https://wiki.zimbra.com/wiki/Security_Center
https://wiki.zimbra.com/wiki/Zimbra_Releases/8.8.15/P23
https://wiki.zimbra.com/wiki/Zimbra_Releases/9.0.0/P16
https://wiki.zimbra.com/wiki/Zimbra_Security_Advisories

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