Note: This bug is displayed in read-only format because the product is no longer active in Red Hat Bugzilla.

For bugs related to Red Hat Enterprise Linux 3 product line. The current stable release is 3.9. For Red Hat Enterprise Linux 6 and above, please visit Red Hat JIRA https://issues.redhat.com/secure/CreateIssue!default.jspa?pid=12332745 to report new issues.

Bug 156996

Summary:	CAN-2004-2069 openssh DoS issue
Product:	Red Hat Enterprise Linux 3	Reporter:	Josh Bressers <bressers>
Component:	openssh	Assignee:	Tomas Mraz <tmraz>
Status:	CLOSED ERRATA	QA Contact:	Brian Brock <bbrock>
Severity:	low	Docs Contact:
Priority:	medium
Version:	3.0	CC:	minfrin
Target Milestone:	---	Keywords:	Security
Target Release:	---
Hardware:	All
OS:	Linux
Whiteboard:	impact=low,public=20040127,reported=bugzilla,reported=20050504
Fixed In Version:	RHSA-2005-550	Doc Type:	Bug Fix
Doc Text:		Story Points:	---
Clone Of:		Environment:
Last Closed:	2005-09-28 14:31:49 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:
Bug Depends On:
Bug Blocks:	156320

Description Josh Bressers 2005-05-05 21:27:22 UTC

This information comes from
https://bugzilla.redhat.com/bugzilla/show_bug.cgi?id=105710#c10

Basically, the MaxStartups (10) and LoginGraceTime (120 seconds) settings are
supposed to defend against DoS, but when run in privilege-separated mode (the
default), OpenSSH server does not properly kill its children after
LoginGraceTime expires. Thus, sshd processes that are still in authentication
phase after LoginGraceTime expires can hang around forever, and you can DoS an
FC2 OpenSSH server with default settings by simply opening up 10 connections to
the server, specifying an SSH key with a passphrase, and never typing the
passphrase.

http://marc.theaimsgroup.com/?l=openssh-unix-dev&m=107520317020444&w=2

Comment 1 Tomas Mraz 2005-05-25 13:04:39 UTC

*** Bug 144799 has been marked as a duplicate of this bug. ***

Comment 2 Josh Bressers 2005-06-02 15:28:32 UTC

Tomas,

Do you know if this issue also affects RHEL4?

My notes say no, but I want to double check.

Comment 3 Tomas Mraz 2005-06-02 18:04:10 UTC

This was fixed upstream before 3.9p1 version was released, so it doesn't affect
RHEL4.

Comment 6 Red Hat Bugzilla 2005-09-28 14:31:50 UTC

An advisory has been issued which should help the problem
described in this bug report. This report is therefore being
closed with a resolution of ERRATA. For more information
on the solution and/or where to find the updated files,
please follow the link below. You may reopen this bug report
if the solution does not work for you.

http://rhn.redhat.com/errata/RHSA-2005-550.html