Open Redirect in Zimbra Collaboration

CVE-2021-34807

An open redirect vulnerability exists in the /preauth Servlet in Zimbra Collaboration Suite through 9.0. To exploit the vulnerability, an attacker would need to have obtained a valid zimbra auth token or a valid preauth token. Once the token is obtained, an attacker could redirect a user to any URL via isredirect=1&redirectURL= in conjunction with the token data (e.g., a valid authtoken= value).

Vulnerability class: Open Redirect

EPSS: 0.010 (58.3th percentile) — read the EPSS interpretation.

CVSS v3 metric

CVSS v3 base score 6.1 (Medium). Vector: CVSS:3.1/AV:N/AC:L/PR:N/UI:R/S:C/C:L/I:L/A:N.

Affected products

Weakness classification (CWE)

References

Frequently asked questions

What is CVE-2021-34807?
CVE-2021-34807 is a medium-severity vulnerability in Zimbra Collaboration, classified under URL Redirection to Untrusted Site (Open Redirect). CVSS score: 6.1/10. Published 2021-07-02.
How severe is CVE-2021-34807?
Medium severity. CVSS v3 base score is 6.1 out of 10.