Bug 1370493 (CVE-2016-7030)

Summary: CVE-2016-7030 ipa: DoS attack against kerberized services by abusing password policy
Product: [Other] Security Response Reporter: Adam Mariš <amaris>
Component: vulnerabilityAssignee: Red Hat Product Security <security-response-team>
Status: CLOSED ERRATA QA Contact:
Severity: medium Docs Contact:
Priority: medium    
Version: unspecifiedCC: cbuissar, dkholia, jcholast, pspacek, pvoborni, rcritten, security-response-team, ssorce
Target Milestone: ---Keywords: Security
Target Release: ---   
Hardware: All   
OS: Linux   
Whiteboard:
Fixed In Version: Doc Type: If docs needed, set a value
Doc Text:
It was discovered that the default IdM password policies that lock out accounts after a certain number of failed login attempts were also applied to host and service accounts. A remote unauthenticated user could use this flaw to cause a denial of service attack against kerberized services.
 Story Points: ---
Clone Of: Environment:
Last Closed: 2017-01-02 11:48:58 UTC Type: ---
Regression: --- Mount Type: ---
Documentation: --- CRM:
Verified Versions: Category: ---
oVirt Team: --- RHEL 7.3 requirements from Atomic Host:
Cloudforms Team: --- Target Upstream Version:
Bug Depends On: 1374638, 1402810, 1402811, 1404690    
Bug Blocks: 1370497, 1395316    
Attachments:
Description Flags
Patch none

Description Adam Mariš 2016-08-26 13:22:25 UTC 
A flaw was found that allows any unauthenticated party to easily run DoS attack against kerberized services in FreeIPA/IdM realm.

FreeIPA contains MIT KDC as its main component + FreeIPA is using custom database driver for the KDC. As a side-effect of implementation, FreeIPA is enforcing password policies for all principals, including services which do not use "password" but keytab with randomly-generated/strong key.

Default password policy locks an account after 5 unsuccessful authentication attempts for 10 minutes. An attacker can use this to simply lock-out any principal, including system services.

Upstream patch : 
https://git.fedorahosted.org/cgit/freeipa.git/commit/?id=6f1d927467e7907fd1991f88388d96c67c9bff61

Additional dependency :
https://git.fedorahosted.org/cgit/freeipa.git/commit/?id=73f33569c8893610e246b2f44a7aeaec872b37e6
Comment 1 Adam Mariš 2016-08-26 13:22:31 UTC 
Acknowledgments:

Name: Petr Spacek (Red Hat)
Comment 12 Cedric Buissart 2016-12-14 12:36:06 UTC 
Created freeipa tracking bugs for this issue:

Affects: fedora-all [bug 1404690]
Comment 13 Cedric Buissart 2016-12-20 09:38:36 UTC 
Comment on attachment 1230758 [details]
Patch

obsoleting patch : see description for list of upstream patches
Comment 14 errata-xmlrpc 2017-01-02 10:54:42 UTC 
This issue has been addressed in the following products:

  Red Hat Enterprise Linux 7

Via RHSA-2017:0001 https://rhn.redhat.com/errata/RHSA-2017-0001.html