CVE-1999-0661: Critical severity TCP Wrappers TCP Wrappers vulnerability

Published Jan 1, 1999
·
Updated

A system is running a version of software that was replaced with a Trojan Horse at one of its distribution points, such as (1) TCP Wrappers 7.6, (2) util-linux 2.9g, (3) wuarchive ftpd (wuftpd) 2.2 and 2.1f, (4) IRC client (ircII) ircII 2.2.9, (5) OpenSSH 3.4p1, or (6) Sendmail 8.12.6.

Affected Software

6 affected components
TCP Wrappers TCP Wrappers
util-linux util-linux
wuarchive wuftpd>=2.1f<=2.2
ircII ircII
OpenSSH OpenSSH
Sendmail Sendmail

Remediation

Recommended actions to resolve this vulnerability, in priority order.

  1. Remove

    Remove OpenSSH from your environment.

    Uninstall the affected OpenSSH package if it is the affected release (e.g., OpenSSH 3.4p1). Do not trust the existing binaries; remove them before reinstalling a verified clean copy.

  2. Remove

    Remove Red Hat Sendmail from your environment.

    Uninstall the affected Sendmail package if it is the affected release (e.g., Sendmail 8.12.6). Remove compromised binaries prior to redeployment.

  3. Remove

    Remove TCP Wrappers from your environment.

    Uninstall the affected TCP Wrappers package if it is the affected release (e.g., TCP Wrappers 7.6). Remove compromised binaries prior to redeployment.

  4. Remove

    Remove Washington University wu-ftpd from your environment.

    Uninstall the affected wu-ftpd package if it is one of the affected releases (e.g., wuftpd 2.2 or 2.1f). Remove compromised binaries prior to redeployment.

  5. Remove

    Remove ircII from your environment.

    Uninstall the affected ircII package if it is the affected release (e.g., ircII 2.2.9). Remove compromised binaries prior to redeployment.

  6. Remove

    Remove util-linux from your environment.

    Uninstall the affected util-linux package if it is the affected release (e.g., util-linux 2.9g). Remove compromised binaries prior to redeployment.

  7. Compensating control

    Isolate potentially affected hosts from the network (or restrict network access) until remediation is complete to prevent further compromise or data exfiltration.

  8. Operational

    Reinstall affected software only from trusted, verified distribution points or known-good media. Verify checksums and cryptographic signatures of all replacement packages before installation. If system binaries were trojanized, consider a full system rebuild from trusted media.

  9. Operational

    Conduct incident response activities: search for indicators of compromise, review logs for unauthorized access, and, if compromise is confirmed or suspected, rotate credentials and keys that may have been exposed.

Event History

Jan 1, 1999
CVE Published
05:00 AM
Data Sourced
05:00 AM
DescriptionWeakness
Data Sourced
05:00 AM
Severity
Data Sourced
via NVD·05:00 AM
DescriptionSeverity
Feb 4, 2000
CVE Published
via MITRE·10:00 AM
Data Sourced
via MITRE·10:00 AM
Description
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Frequently Asked Questions

1

What is the severity of CVE-1999-0661?

CVE-1999-0661 is considered a significant security vulnerability due to the risk of a Trojan Horse being distributed through compromised software.

2

How do I fix CVE-1999-0661?

To mitigate CVE-1999-0661, you should replace any affected software versions with legitimate updates from trusted sources.

3

Which software versions are affected by CVE-1999-0661?

CVE-1999-0661 affects versions of TCP Wrappers 7.6, util-linux 2.9g, wu-ftpd versions from 2.1f to 2.2, and various versions of IRC client ircII, OpenSSH, and Sendmail.

4

How can I determine if my system is vulnerable to CVE-1999-0661?

You can determine if your system is vulnerable to CVE-1999-0661 by checking the installed versions of the affected software against the known vulnerable versions.

5

What are the potential risks of CVE-1999-0661?

The potential risks of CVE-1999-0661 include unauthorized access to system resources and data exfiltration due to the presence of Trojan Horse software.

Contact

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