CVE-2021-34807
mediumpriority · track · 24EPSS 0.010 · 62 %ileEUUSEPSS · scored 2026-10-28
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
Technical severity, 0–10. One row per scoring source.
base score 0–10 · higher = more severe · hover a vector to decode
weaknesses
The CWE weakness classes this flaw belongs to.
affected products (4)
Products and version ranges known to be affected.
also known as (3)
Other names and identifiers for this entity.
sources
Which sources assert this record, and when.
references (13)
External citations — patches, advisories, analysis.
- https://wiki.zimbra.com/wiki/Security_Centercnnvd
- https://wiki.zimbra.com/wiki/Zimbra_Releases/8.8.15/P23cnnvd
- https://wiki.zimbra.com/wiki/Zimbra_Releases/9.0.0/P16cnnvd
- https://wiki.zimbra.com/wiki/Zimbra_Security_Advisoriescnnvd
- https://www.cybersecurity-help.cz/vdb/SB2021072806cnnvd
- https://wiki.zimbra.com/wiki/Security_Centerenisa_euvd
- https://wiki.zimbra.com/wiki/Zimbra_Releases/8.8.15/P23enisa_euvd
- https://wiki.zimbra.com/wiki/Zimbra_Releases/9.0.0/P16enisa_euvd
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