Bug 57859

Summary:	password error delay reveals existing/non-existing accounts
Product:	[Retired] Red Hat Linux	Reporter:	Florin Andrei <florin>
Component:	openssh	Assignee:	Tomas Mraz <tmraz>
Status:	CLOSED CURRENTRELEASE	QA Contact:	Brian Brock <bbrock>
Severity:	medium	Docs Contact:
Priority:	medium
Version:	7.2
Target Milestone:	---
Target Release:	---
Hardware:	i686
OS:	Linux
Whiteboard:
Fixed In Version:		Doc Type:	Bug Fix
Doc Text:		Story Points:	---
Clone Of:		Environment:
Last Closed:	2005-02-03 09:57:53 UTC	Type:	---
Regression:	---	Mount Type:	---
Documentation:	---	CRM:
Verified Versions:		Category:	---
oVirt Team:	---	RHEL 7.3 requirements from Atomic Host:
Cloudforms Team:	---	Target Upstream Version:
Embargoed:

Description Florin Andrei 2001-12-28 19:06:08 UTC

From Bugzilla Helper:
User-Agent: Mozilla/5.0 (X11; U; Linux i686; en-US; rv:0.9.5) Gecko/20011014

Description of problem:
When you login by ssh to a host and the password fails, there's a small
delay before getting the password prompt again, which prevents bruteforce
attacks.
But if you try to login to a non-existent username, the password prompt
returns immediately.
This allows remote attackers to guess usernames.

Version-Release number of selected component (if applicable):


How reproducible:
Always

Steps to Reproduce:
1. ssh some-nonexistent-username@hostname
2. enter some bogus pass
3.
	

Actual Results:  you get the password prompt again immediately

Expected Results:  there should be a delay before getting the prompt

Additional info:

tested on Red Hat 7.2 with openssh-3.0.2p1

Comment 1 Damien Miller 2001-12-30 07:23:47 UTC

> Expected Results:  there should be a delay before getting the prompt

Why slow down valid users? 

If anything, there should be no delay for invalid accounts, but this facilitates
password guessing.

Comment 2 Tomas Mraz 2005-02-03 09:57:53 UTC

In current Fedora Core (openssh-3.9p1) the non existing accounts give
the same delay as mistaken passwords on existing accounts.