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
Published · last modified .
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.
EPSS exploit prediction
EPSS: 0.010 (60.7th percentile), scored .
Very low probability of exploitation in the next 30 days; routine patching cadence is appropriate. 61st percentile — 60.7% of CVEs in the catalogue have a lower EPSS than this one. How to read EPSS.
EPSS over last 30 days · oldest: 0.010 · newest: 0.010 · change: 0.000
Affected products
- Zimbra Collaboration — versions 8.8.15, 9.0.0
Weakness classification (CWE)
References
- wiki.zimbra.com/wiki/Zimbra_Security_Advisories (Vendor Advisory)
- wiki.zimbra.com/wiki/Security_Center (Release Notes, Vendor Advisory)
- wiki.zimbra.com/wiki/Zimbra_Releases/9.0.0/P16 (Release Notes, Vendor Advisory)
- wiki.zimbra.com/wiki/Zimbra_Releases/8.8.15/P23 (Release Notes, Vendor Advisory)
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.