CVE-2021-20110

Due to Manage Engine Asset Explorer Agent 1.0.34 not validating HTTPS certificates, an attacker on the network can statically configure their IP address to match the Asset Explorer's Server IP address. This will allow an attacker to send a NEWSCAN request to a listening agent on the network as well as receive the agent's HTTP request verifying its authtoken. In httphandler.cpp, the agent reaching out over HTTP is vulnerable to an Integer Overflow, which can be turned into a Heap Overflow allowing for remote code execution as NT AUTHORITY/SYSTEM on the agent machine. The Integer Overflow occurs when receiving POST response from the Manage Engine server, and the agent calling "HttpQueryInfoW" in order to get the "Content-Length" size from the incoming POST request. This size is taken, but multiplied to a larger amount. If an attacker specifies a Content-Length size of 1073741823 or larger, this integer arithmetic will wrap the value back around to smaller integer, then calls "calloc" with this size to allocate memory. The following API "InternetReadFile" will copy the POST data into this buffer, which will be too small for the contents, and cause heap overflow.

CVSS v3.0 9.8 CRITICAL
CVSS v2.0 10.0 HIGH

9.8^/10

CVSS v3.0 : CRITICAL

Vector :

Exploitability : 3.9 / Impact : 5.9

Attack Vector NETWORK

Attack Complexity LOW

Privileges Required NONE

User Interaction NONE

Confidentiality Impact HIGH

Integrity Impact HIGH

Availability Impact HIGH

Scope UNCHANGED

10.0^/10

CVSS v2.0 : HIGH

Vector : AV:N/AC:L/Au:N/C:C/I:C/A:C

Exploitability : 10.0 / Impact : 10.0

Access Vector NETWORK

Access Complexity LOW

Authentication NONE

Confidentiality Impact COMPLETE

Integrity Impact COMPLETE

Availability Impact COMPLETE

References

Link	Resource
https://www.tenable.com/security/research/tra-2021-31	Third Party Advisory

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Configurations

Configuration 1 (hide)

cpe:2.3:a:zohocorp:manageengine_assetexplorer:1.0.34:*:*:*:*:*:*:*

Information

Published : 2021-07-19 08:15

Updated : 2021-07-28 06:46

NVD link : CVE-2021-20110

Mitre link : CVE-2021-20110

JSON object : View

CWE

CWE-295

Improper Certificate Validation

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Products Affected

zohocorp

manageengine_assetexplorer

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