Medium severity · published Dec 30, 2020
CVE-2020-5809
A stored XSS vulnerability exists in Umbraco CMS <= 8.9.1 or current
5.4
CVSS
0.7%
EPSS
No
On KEV
Description
A stored XSS vulnerability exists in Umbraco CMS <= 8.9.1 or current. An authenticated user can inject arbitrary JavaScript code into iframes when editing content using the TinyMCE rich-text editor, as TinyMCE is configured to allow iframes by default in Umbraco CMS.
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)0.7% · higher than 52% of CVEs
Exploited in the wildNo evidence yet
CISA KEVNot listed
Ransomware campaign useNot known
Affected products
Which versions
UC
Umbraco Cms · Umbraco
through 8.9.1 · source: NVD
References
NVD
https://nvd.nist.gov/vuln/detail/CVE-2020-5809
CVE.org
https://www.cve.org/CVERecord?id=CVE-2020-5809
Exploit
https://www.tenable.com/security/research/tra-2020-59
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