Linux Distros Unpatched Vulnerability : CVE-2021-20110

critical Nessus Plugin ID 262792

Synopsis

The Linux/Unix host has one or more packages installed with a vulnerability that the vendor indicates will not be patched.

Description

The Linux/Unix host has one or more packages installed that are impacted by a vulnerability without a vendor supplied patch available.

- 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. (CVE-2021-20110)

Note that Nessus relies on the presence of the package as reported by the vendor.

Solution

There is no known solution at this time.

See Also

https://ubuntu.com/security/CVE-2021-20110

Plugin Details

Severity: Critical

ID: 262792

File Name: unpatched_CVE_2021_20110.nasl

Version: 1.1

Type: local

Agent: unix

Family: Misc.

Published: 9/10/2025

Updated: 9/10/2025

Supported Sensors: Frictionless Assessment AWS, Frictionless Assessment Azure, Frictionless Assessment Agent, Nessus Agent, Agentless Assessment, Nessus

Risk Information

VPR

Risk Factor: Medium

Score: 5.9

CVSS v2

Risk Factor: Critical

Base Score: 10

Temporal Score: 7.4

Vector: CVSS2#AV:N/AC:L/Au:N/C:C/I:C/A:C

CVSS Score Source: CVE-2021-20110

CVSS v3

Risk Factor: Critical

Base Score: 9.8

Temporal Score: 8.5

Vector: CVSS:3.0/AV:N/AC:L/PR:N/UI:N/S:U/C:H/I:H/A:H

Temporal Vector: CVSS:3.0/E:U/RL:O/RC:C

Vulnerability Information

CPE: cpe:/o:canonical:ubuntu_linux:22.04:-:lts, cpe:/o:canonical:ubuntu_linux:24.04:-:lts, p-cpe:/a:canonical:ubuntu_linux:due, cpe:/o:canonical:ubuntu_linux:25.04

Required KB Items: Host/local_checks_enabled, Host/cpu, global_settings/vendor_unpatched, Host/OS/identifier

Exploit Ease: No known exploits are available

Vulnerability Publication Date: 7/16/2021

Reference Information

CVE: CVE-2021-20110