Medium severity · published Jul 2, 2021
CVE-2021-34807
An open redirect vulnerability exists in the /preauth Servlet in Zimbra Collaboration Suite through 9.0
6.1
CVSS
1%
EPSS
No
On KEV
Description
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).
CVSS vector
CVSS:3.1/AV:N/AC:L/PR:N/UI:R/S:C/C:L/I:L/A:N
Attack vector
Network
Complexity
Low
Privileges
None
User interaction
Required
Confidentiality
Low
Integrity
Low
Availability
None
Scope
Changed
Exploitation
Is it being used?
Exploit prediction (EPSS)1.0% · higher than 62% of CVEs
Exploited in the wildNo evidence yet
CISA KEVNot listed
Ransomware campaign useNot known
Affected products
Which versions
CO
Collaboration · Zimbra
before 8.8.15; 8.8.15; 8.8.15; 8.8.15; 8.8.15; 8.8.15; +34 more · source: NVD
References
NVD
https://nvd.nist.gov/vuln/detail/CVE-2021-34807
CVE.org
https://www.cve.org/CVERecord?id=CVE-2021-34807
Release Notes
https://wiki.zimbra.com/wiki/Security_Center
Release Notes
https://wiki.zimbra.com/wiki/Zimbra_Releases/8.8.15/P23
Release Notes
https://wiki.zimbra.com/wiki/Zimbra_Releases/9.0.0/P16
Vendor Advisory
https://wiki.zimbra.com/wiki/Zimbra_Security_Advisories
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