CVE-1999-0775: Critical severity Cisco IOS vulnerability

Published Jun 10, 1999
·
Updated

Cisco Gigabit Switch routers running IOS allow remote attackers to forward unauthorized packets due to improper handling of the "established" keyword in an access list.

Affected Software

2 affected components
Cisco IOS=11.2\(15\)g
Cisco IOS=11.2\(14\)gs2

Remediation

Recommended actions to resolve this vulnerability, in priority order.

  1. Configuration

    Do not use the 'established' keyword in access lists on affected Cisco IOS devices; remove or replace access-list entries that use 'established' until a vendor-supplied fix is available.

    Cisco IOS (access-list) 'established' keyword = avoid/remove

Event History

Jun 10, 1999
CVE Published
04:00 AM
Data Sourced
via NVD·04:00 AM
DescriptionSeverityAffected Software
Jan 18, 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-1999-0775?

CVE-1999-0775 is classified as a high severity vulnerability due to the potential for remote attackers to forward unauthorized packets.

2

How do I fix CVE-1999-0775?

To mitigate CVE-1999-0775, ensure that proper access controls are configured in your Cisco IOS access lists.

3

What is the impact of CVE-1999-0775?

The impact of CVE-1999-0775 includes unauthorized packet forwarding, which can lead to data interception or network disruption.

4

Which versions of Cisco IOS are affected by CVE-1999-0775?

CVE-1999-0775 affects Cisco IOS versions 11.2(15)g and 11.2(14)gs2.

5

What is the nature of the vulnerability in CVE-1999-0775?

The nature of the vulnerability in CVE-1999-0775 is improper handling of the 'established' keyword in access lists, allowing malicious actions.

Contact

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