Bug 1665296 (CVE-2018-20217) - CVE-2018-20217 krb5: Reachable assertion in the KDC using S4U2Self requests
Summary: CVE-2018-20217 krb5: Reachable assertion in the KDC using S4U2Self requests
Status: NEW
Alias: CVE-2018-20217
Product: Security Response
Classification: Other
Component: vulnerability
Version: unspecified
Hardware: All
OS: Linux
Target Milestone: ---
Assignee: Red Hat Product Security
QA Contact:
Whiteboard: impact=moderate,public=20181202,repor...
Keywords: Security
Depends On: 1673017 1665297 1673016
Blocks: 1665299
TreeView+ depends on / blocked
Reported: 2019-01-10 21:45 UTC by Laura Pardo
Modified: 2019-06-14 09:15 UTC (History)
9 users (show)

Clone Of:
Last Closed:

Attachments (Terms of Use)

Description Laura Pardo 2019-01-10 21:45:52 UTC
A vulnerability was found in in the KDC in MIT Kerberos 5 (aka krb5) before 1.17. An authenticated user who can obtain a TGT using an older encryption type (DES, DES3, or RC4) can cause an assertion failure in the KDC by sending an S4U2Self request.


Upstream Patch:

Comment 1 Laura Pardo 2019-01-10 21:46:24 UTC
Created krb5 tracking bugs for this issue:

Affects: fedora-all [bug 1665297]

Comment 7 Rama 2019-02-20 22:45:39 UTC
Why is it that Status is New and Fixed In says 1.17? Is this bug really fixed in RHEL 7?
If so, is there a CentOS 7.x RPM with this fix already?

Comment 8 Robbie Harwood 2019-02-21 17:04:38 UTC
Hi Rama, 1.17 is the krb5 version that it's fixed in upstream.

This is the RHEL/Fedora bugtracker; CentOS bugs are tracked separately (by different people) at https://bugs.centos.org

Comment 10 Rama 2019-03-01 06:19:48 UTC
Hi Robbie,

We currently bundle krb5-libs-1.15.1-19.el7.x86_64 and krb5-devel-1.15.1-19.el7.x86_64 on the top of the CentOS 7.5.1804. 
And we are trying to fix cve-2018-20217. Idea is to apply the upstream patch onto this source and rebuild source RPM and RPM for 1.17.

I will be raising this question on CentOS forum as suggested.
Would appreciate if you can share your thoughts as you are involved with krb5 development.

Comment 12 Joshua Padman 2019-05-15 22:55:17 UTC
This vulnerability is out of security support scope for the following product:
 * Red Hat Enterprise Application Platform 6

Please refer to https://access.redhat.com/support/policy/updates/jboss_notes for more details.

Note You need to log in before you can comment on or make changes to this bug.