CVE-1999-0740: Medium severity redhat Linux vulnerability

Published Aug 19, 1999
·
Updated

Remote attackers can cause a denial of service on Linux in.telnetd telnet daemon through a malformed TERM environmental variable.

Affected Software

3 affected components
redhat Linux=5.2
redhat Linux=4.2
redhat Linux=6.0

Remediation

Recommended actions to resolve this vulnerability, in priority order.

  1. Remove

    Remove Red Hat in.telnetd (telnet daemon) from your environment.

    Uninstall the in.telnetd/telnet daemon package from affected systems if the service is not required.

  2. Configuration

    Disable the telnet service to prevent remote connections (use your distribution's service management tools, e.g., systemctl disable --now telnet.socket or the equivalent).

    in.telnetd (telnet daemon on Red Hat Linux) service_enabled = false
  3. Compensating control

    Restrict network access to the telnet service (TCP port 23) at the network perimeter or host-based firewall so only trusted management hosts can reach it.

  4. Operational

    Monitor vendor/security advisories and apply any vendor-provided patch or update for in.telnetd as soon as it becomes available.

Event History

Aug 19, 1999
CVE Published
04:00 AM
Data Sourced
via NVD·04:00 AM
DescriptionSeverityAffected Software
Mar 22, 2000
CVE Published
via MITRE·10:00 AM
Data Sourced
via MITRE·10:00 AM
Description

Frequently Asked Questions

1

What is the severity of CVE-1999-0740?

CVE-1999-0740 is considered a high-severity vulnerability as it allows remote attackers to cause a denial of service.

2

How do I fix CVE-1999-0740?

To fix CVE-1999-0740, it is recommended to update to a patched version of the telnet daemon or disable the telnet service.

3

Which systems are vulnerable to CVE-1999-0740?

CVE-1999-0740 affects Red Hat Linux versions 4.2, 5.2, and 6.0.

4

What type of attack is associated with CVE-1999-0740?

CVE-1999-0740 is associated with a denial of service attack facilitated through a malformed TERM environmental variable.

5

Can CVE-1999-0740 be exploited remotely?

Yes, CVE-1999-0740 can be exploited remotely by attackers to disrupt telnet services.

Contact

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