High severity · published Jul 30, 2021
CVE-2021-36766
Concrete5 through 8.5.5 deserializes Untrusted Data
7.2
CVSS
3.7%
EPSS
No
On KEV
Description
Concrete5 through 8.5.5 deserializes Untrusted Data. The vulnerable code is located within the controllers/single_page/dashboard/system/environment/logging.php Logging::update_logging() method. User input passed through the logFile request parameter is not properly sanitized before being used in a call to the file_exists() PHP function. This can be exploited by malicious users to inject arbitrary PHP objects into the application scope (PHP Object Injection via phar:// stream wrapper), allowing them to carry out a variety of attacks, such as executing arbitrary PHP code.
CVSS vector
CVSS:3.1/AV:N/AC:L/PR:H/UI:N/S:U/C:H/I:H/A:H
Attack vector
Network
Complexity
Low
Privileges
High
User interaction
None
Confidentiality
High
Integrity
High
Availability
High
Scope
Unchanged
Exploitation
Is it being used?
Exploit prediction (EPSS)3.7% · higher than 90% of CVEs
Exploited in the wildNo evidence yet
CISA KEVNot listed
Ransomware campaign useNot known
Affected products
Which versions
CC
Concrete Cms · Concretecms
before 8.5.6 · source: NVD
References
NVD
https://nvd.nist.gov/vuln/detail/CVE-2021-36766
CVE.org
https://www.cve.org/CVERecord?id=CVE-2021-36766
Exploit
http://packetstormsecurity.com/files/163564/Concrete5-8.5.5-Phar-Deserialization.html
Exploit
http://seclists.org/fulldisclosure/2021/Jul/36
Permissions Required
https://hackerone.com/reports/1063039
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