Bug 1081338 - (CVE-2014-2653) CVE-2014-2653 openssh: failure to check DNS SSHFP records in certain scenarios
CVE-2014-2653 openssh: failure to check DNS SSHFP records in certain scenarios
Status: CLOSED ERRATA
Product: Security Response
Classification: Other
Component: vulnerability (Show other bugs)
unspecified
All Linux
medium Severity medium
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Assigned To: Red Hat Product Security
impact=moderate,public=20140324,repor...
: Reopened, Security
Depends On: 1081341 1081343 1101171 1101172
Blocks: 1081345 1101912 1121513
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Reported: 2014-03-26 23:51 EDT by Murray McAllister
Modified: 2015-07-31 03:17 EDT (History)
11 users (show)

See Also:
Fixed In Version:
Doc Type: Bug Fix
Doc Text:
It was discovered that OpenSSH clients did not correctly verify DNS SSHFP records. A malicious server could use this flaw to force a connecting client to skip the DNS SSHFP record check and require the user to perform manual host verification of the DNS SSHFP record.
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Last Closed: 2015-03-05 05:15:32 EST
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RHEL 7.3 requirements from Atomic Host:
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Description Murray McAllister 2014-03-26 23:51:21 EDT
Matthew Vernon found that the OpenSSH client may fail to check DNS SSHFP records. When using DNS SSHFP records, if the server offers the client a certificate that the client does not accept, the client does not then verify the DNS SSHFP records. A host verification prompt is still displayed before connecting. A malicious server could possibly use this flaw to disable DNS SSHFP checking and trick a client into connecting to it, if the user accepts 'yes' at the host verification prompt.

Original report including a possible patch:

https://bugs.debian.org/cgi-bin/bugreport.cgi?bug=742513
Comment 1 Murray McAllister 2014-03-26 23:53:00 EDT
Created openssh tracking bugs for this issue:

Affects: fedora-all [bug 1081341]
Comment 4 Fedora Update System 2014-05-21 19:23:39 EDT
openssh-6.4p1-4.fc20 has been pushed to the Fedora 20 stable repository.  If problems still persist, please make note of it in this bug report.
Comment 10 Fedora Update System 2014-06-09 22:51:06 EDT
openssh-6.2p2-8.fc19 has been pushed to the Fedora 19 stable repository.  If problems still persist, please make note of it in this bug report.
Comment 14 Martin Prpic 2014-10-06 04:47:18 EDT
IssueDescription:

It was discovered that OpenSSH clients did not correctly verify DNS SSHFP records. A malicious server could use this flaw to force a connecting client to skip the DNS SSHFP record check and require the user to perform manual host verification of the DNS SSHFP record.
Comment 15 errata-xmlrpc 2014-10-14 03:39:49 EDT
This issue has been addressed in the following products:

  Red Hat Enterprise Linux 6

Via RHSA-2014:1552 https://rhn.redhat.com/errata/RHSA-2014-1552.html
Comment 16 Huzaifa S. Sidhpurwala 2014-10-16 02:34:33 EDT
Statement:

The Red Hat Security Response Team has rated this issue as having Moderate security impact. This issue is not planned to be fixed in Red Hat Enterprise Linux 5 as it is now in Production 3 Phase of the support and maintenance life cycle, https://access.redhat.com/support/policy/updates/errata/
Comment 22 errata-xmlrpc 2015-03-05 04:27:38 EST
This issue has been addressed in the following products:

  Red Hat Enterprise Linux 7

Via RHSA-2015:0425 https://rhn.redhat.com/errata/RHSA-2015-0425.html

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