Medium severity · published Jul 2, 2021
CVE-2021-35208
An issue was discovered in ZmMailMsgView.js in the Calendar Invite component in Zimbra Collaboration Suite 8.8.x before 8.8.15 Patch 23
5.4
CVSS
1.3%
EPSS
No
On KEV
Description
An issue was discovered in ZmMailMsgView.js in the Calendar Invite component in Zimbra Collaboration Suite 8.8.x before 8.8.15 Patch 23. An attacker could place HTML containing executable JavaScript inside element attributes. This markup becomes unescaped, causing arbitrary markup to be injected into the document.
CVSS vector
CVSS:3.1/AV:N/AC:L/PR:L/UI:R/S:C/C:L/I:L/A:N
Attack vector
Network
Complexity
Low
Privileges
Low
User interaction
Required
Confidentiality
Low
Integrity
Low
Availability
None
Scope
Changed
Exploitation
Is it being used?
Exploit prediction (EPSS)1.3% · higher than 70% of CVEs
Exploited in the wildNo evidence yet
CISA KEVNot listed
Ransomware campaign useNot known
Affected products
Which versions
CO
Collaboration · Zimbra
8.8 before 8.8.15; 8.8.15; 8.8.15; 8.8.15; 8.8.15; 8.8.15; +18 more · source: NVD
References
NVD
https://nvd.nist.gov/vuln/detail/CVE-2021-35208
CVE.org
https://www.cve.org/CVERecord?id=CVE-2021-35208
Exploit
https://blog.sonarsource.com/zimbra-webmail-compromise-via-email
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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