BSD Telnet Client missing encryption

CVSS Meta Temp Score
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CTI Interest Score
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A vulnerability classified as critical was found in BSD (affected version unknown). Affected by this vulnerability is an unknown function of the component Telnet Client. The manipulation with an unknown input leads to a weak encryption vulnerability. The CWE definition for the vulnerability is CWE-311. As an impact it is known to affect confidentiality. The summary by CVE is:

vulnerability in bsd telnet client with encryption and kerberos 4 authentication allows remote attackers to decrypt the session via sniffing.

The weakness was shared 03/03/1995 by FIRST as CA-1995-03 as confirmed advisory ( It is possible to read the advisory at This vulnerability is known as CVE-1999-1098. The exploitation appears to be easy. The attack can be launched remotely. The exploitation doesn't need any form of authentication. The technical details are unknown and an exploit is not publicly available. The attack technique deployed by this issue is T1600 according to MITRE ATT&CK.

It is possible to mitigate the problem by adding an authentication mechanism.

The vulnerability is also documented in the databases at SecurityFocus (BID 139) and X-Force (516). Additional details are provided at



CPE 2.3infoedit

CPE 2.2infoedit


VulDB Meta Base Score: 5.3
VulDB Meta Temp Score: 5.2

VulDB Base Score: 5.3
VulDB Temp Score: 5.2
VulDB Vector: 🔍
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Class: Weak encryption
CWE: CWE-311
ATT&CK: T1600

Local: No
Remote: Yes

Availability: 🔍
Status: Not defined

Price Prediction: 🔍
Current Price Estimation: 🔍


Threat Intelligenceinfoedit

Threat: 🔍
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Recommended: Authentication
Status: 🔍

0-Day Time: 🔍


03/03/1995 🔍
03/03/1995 +0 days 🔍
12/31/1998 +1399 days 🔍
04/03/2004 +1920 days 🔍
06/17/2014 +3726 days 🔍
04/03/2019 +1751 days 🔍


Advisory: CA-1995-03
Researcher: FIRST
Status: Confirmed

CVE: CVE-1999-1098 (🔍)
SecurityFocus: 139 - Berkeley Telnet Kerberos Vulnerability
X-Force: 516 - Berkeley Telnet clients that support encryption can be decrypted easily
OSVDB: 4881 - BSD Telnet Client Kerberos Session Sniffing

Misc.: 🔍


Created: 06/17/2014 03:43 PM
Updated: 04/03/2019 02:10 PM
Changes: (1) advisory_person_nickname
Complete: 🔍


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