Microsoft Windows Server 2003, when time restrictions are in effect for user accounts, generates different error messages for failed login attempts with a valid user name than for those with an invalid user name, which allows context-dependent attackers to determine valid Active Directory account names.
This is a vulnerability exploitable with adjacent network access and requires the attacker to have
access to either the broadcast or collision domain of the vulnerable software. Examples of
local networks include local IP subnet, Bluetooth, IEEE 802.11, and local Ethernet
Specialized access conditions exist. For example,
in most configurations, the attacking party must already have elevated privileges or spoof additional systems
in addition to the attacking system (e.g., DNS hijacking).
The attack depends on social engineering methods that would be easily detected by knowledgeable people.
For example, the victim must perform several suspicious or atypical actions.
The vulnerable configuration is seen very rarely in practice.
If a race condition exists, the window is very narrow.
Authentication is not required to access and exploit the vulnerability.
There is considerable informational disclosure. Access to some system files is
possible, but the attacker does not have control over what is obtained, or the scope of
the loss is constrained. An example is a vulnerability that divulges only certain tables
in a database.
There is no impact to the integrity of the system.
There is no impact to the availability of the system.
NIST (National Institute of Standards and Technology) NVD (National Vulnerability Database)