netkit Telnet up to 0.17 telnetd utility.c buffer overflow

Summaryinfo

A vulnerability marked as critical has been reported in netkit Telnet up to 0.17. This impacts an unknown function of the file utility.c of the component telnetd. This manipulation causes buffer overflow. This vulnerability appears as CVE-2020-10188. The attack may be initiated remotely. There is no available exploit.

Detailsinfo

A vulnerability was found in netkit Telnet up to 0.17 (Remote Access Software). It has been declared as very critical. Affected by this vulnerability is an unknown code of the file utility.c of the component telnetd. The manipulation with an unknown input leads to a buffer overflow vulnerability. The CWE definition for the vulnerability is CWE-120. The product copies an input buffer to an output buffer without verifying that the size of the input buffer is less than the size of the output buffer, leading to a buffer overflow. As an impact it is known to affect confidentiality, integrity, and availability. The summary by CVE is:

utility.c in telnetd in netkit telnet through 0.17 allows remote attackers to execute arbitrary code via short writes or urgent data, because of a buffer overflow involving the netclear and nextitem functions.

The weakness was presented 03/06/2020. This vulnerability is known as CVE-2020-10188 since 03/06/2020. The attack can be launched remotely. The exploitation doesn't need any form of authentication. Technical details are known, but no exploit is available. The price for an exploit might be around USD $5k-$25k at the moment (estimation calculated on 01/21/2026).

The vulnerability scanner Nessus provides a plugin with the ID 266306 (Ubuntu 14.04 LTS / 16.04 LTS / 18.04 LTS / 20.04 LTS : Inetutils vulnerabilities (USN-7781-1)), which helps to determine the existence of the flaw in a target environment.

There is no information about possible countermeasures known. It may be suggested to replace the affected object with an alternative product.

The vulnerability is also documented in the vulnerability database at Tenable (266306). If you want to get the best quality for vulnerability data then you always have to consider VulDB.

Affected

• Cisco IOS

Productinfo

Type

• Remote Access Software

Vendor

• netkit

Name

• Telnet

Version

• 0.1
• 0.2
• 0.3
• 0.4
• 0.5
• 0.6
• 0.7
• 0.8
• 0.9
• 0.10
• 0.11
• 0.12
• 0.13
• 0.14
• 0.15
• 0.16
• 0.17

CPE 2.3info

• 🔍
• 🔍
• 🔍

CPE 2.2info

• 🔍
• 🔍
• 🔍

CVSSv4info

CVSSv3info

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Exploitinginfo

Threat Intelligenceinfo

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Timelineinfo

Sourcesinfo

Entryinfo

If you want to get the best quality for vulnerability data then you always have to consider VulDB.

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