CVE-2003-0512: Medium severity Cisco IOS vulnerability

Published Jul 29, 2003
·
Updated

Cisco IOS 12.2 and earlier generates a "% Login invalid" message instead of prompting for a password when an invalid username is provided, which allows remote attackers to identify valid usernames on the system and conduct brute force password guessing, as reported for the Aironet Bridge.

Affected Software

9 affected components
Cisco IOS=12.0\(24\)s1
Cisco IOS=12.0\(24.2\)s
Cisco IOS=12.2\(11\)ja1
Cisco IOS=12.2\(14.5\)
Cisco IOS=12.2\(14.5\)t
Cisco IOS=12.2\(15\)zn
Cisco IOS=12.2\(15.1\)s
Cisco IOS=12.2\(16\)b
Cisco IOS=12.2\(16.1\)b

Event History

Jul 29, 2003
CVE Published
via MITRE·08:00 AM
Data Sourced
via MITRE·08:00 AM
Description
Aug 27, 2003
Data Sourced
via NVD·04:00 AM
DescriptionSeverityWeaknessAffected Software

Frequently Asked Questions

1

What access does an attacker need to exploit this issue?

An attacker can probe the login service remotely without authentication. Supplying invalid usernames produces a distinct "% Login invalid" response that can be used to identify valid accounts.

2

What is the practical impact of confirming valid usernames?

Valid username enumeration can make brute-force password guessing more efficient by letting an attacker focus attempts on known accounts. The issue does not itself provide authentication bypass or account access.

3

Which systems are affected?

The provided information identifies Cisco IOS 12.2 and earlier, with the behavior reported for the Aironet Bridge.

Contact

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