[LACNIC/Seguridad] New vulnerability in ISC BIND can cause named to crash

Lucimara Desiderá lucimara en cert.br
Mie Ene 17 12:29:44 BRST 2018


CVE-2017-3145: Improper fetch cleanup sequencing in the resolver can
cause named to crash

Author: ISC Support Reference Number: AA-01542 Views: 6251 Created:
2018-01-16 14:25 Last Updated: 2018-01-16 20:24 	0 Rating/ Voters 	

Improper sequencing during cleanup can lead to a use-after-free error,
triggering an assertion failure and crash in named.

CVE: 		   CVE-2017-3145
Document Version:  2.0
Posting date: 	   16 January 2018
Program Impacted:  BIND
Versions affected: 9.0.0 to 9.8.x, 9.9.0 to 9.9.11, 9.10.0 to 9.10.6,
                   9.11.0 to 9.11.2, 9.9.3-S1 to 9.9.11-S1,
                   9.10.5-S1 to 9.10.6-S1, 9.12.0a1 to 9.12.0rc1
Severity:          High
Exploitable: 	   Remotely


BIND was improperly sequencing cleanup operations on upstream recursion
fetch contexts, leading in some cases to a use-after-free error that can
trigger an assertion failure and crash in named.


While this bug has existed in BIND since 9.0.0, there are no known code
paths leading to it in ISC releases prior to those containing the fix
for CVE-2017-3137.  Thus while all instances of BIND ought to be
patched, only ISC versions [9.9.9-P8 to 9.9.11, 9.10.4-P8 to 9.10.6,
9.11.0-P5 to 9.11.2, 9.9.9-S10 to 9.9.11-S1, 9.10.5-S1 to 9.10.6-S1, and
9.12.0a1 to 9.12.0rc1] acting as DNSSEC validating resolvers are
currently known to crash due to this bug.  The known crash is an
assertion failure in netaddr.c.

CVSS Score:  7.5

CVSS Vector:  CVSS:3.0/AV:N/AC:L/PR:N/UI:N/S:U/C:N/I:N/A:H

For more information on the Common Vulnerability Scoring System and to
obtain your specific environmental score please visit:


If an operator is experiencing crashes due to this, temporarily
disabling DNSSEC validation can be used to avoid the known problematic
code path while replacement builds are prepared.

Active exploits:

No known active exploits but crashes due to this bug have been reported
by multiple parties.

Solution:  Upgrade to the patched release most closely related to your
current version of BIND.  These can all be downloaded from

    BIND 9 version 9.9.11-P1
    BIND 9 version 9.10.6-P1
    BIND 9 version 9.11.2-P1
    BIND 9 version 9.12.0rc2

BIND Supported Preview Edition is a special feature preview branch of
BIND provided to eligible ISC support customers.

    BIND 9 version 9.9.11-S2
    BIND 9 version 9.10.6-S2

Acknowledgements: ISC would like to thank Jayachandran Palanisamy of
Cygate AB for making us aware of this vulnerability.

Document Revision History:

1.0 Advance Notification, 09 January 2018
1.1 Packager Notification, added acknowledgement,  15 January 2018
2.0 Public Release, 16 January 2018

Related Documents:

See our BIND9 Security Vulnerability Matrix at
https://kb.isc.org/article/AA-00913 for a complete listing of Security
Vulnerabilities and versions affected.

If you'd like more information on ISC Subscription Support and Advance
Security Notifications, please visit http://www.isc.org/support/.

Do you still have questions?  Questions regarding this advisory should
go to security-officer en isc.org.  To report a new issue, please encrypt
your message using security-officer en isc.org's PGP key which can be found
https://www.isc.org/downloads/software-support-policy/openpgp-key/.  If
you are unable to use encrypted email, you may also report new issues
at: https://www.isc.org/community/report-bug/.

Note: ISC patches only currently supported versions. When possible we
indicate EOL versions affected.  (For current information on which
versions are actively supported, please see http://www.isc.org/downloads/).

ISC Security Vulnerability Disclosure Policy:  Details of our current
security advisory policy and practice can be found here:

This Knowledge Base article https://kb.isc.org/article/AA-01542 is the
complete and official security advisory document.

Legal Disclaimer:

Internet Systems Consortium (ISC) is providing this notice on an "AS IS"
basis. No warranty or guarantee of any kind is expressed in this notice
and none should be implied. ISC expressly excludes and disclaims any
warranties regarding this notice or materials referred to in this
notice, including, without limitation, any implied warranty of
merchantability, fitness for a particular purpose, absence of hidden
defects, or of non-infringement. Your use or reliance on this notice or
materials referred to in this notice is at your own risk. ISC may change
this notice at any time.  A stand-alone copy or paraphrase of the text
of this document that omits the document URL is an uncontrolled copy.
Uncontrolled copies may lack important information, be out of date, or
contain factual errors.

© 2001-2018 Internet Systems Consortium

For assistance with problems and questions for which you have not been
able to find an answer in our Knowledge Base, we recommend searching our
community mailing list archives and/or posting your question there (you
will need to register there first for your posts to be accepted). The
bind-users and the dhcp-users lists particularly have a long-standing
and active membership.

ISC relies on the financial support of the community to fund the
development of its open source software products. If you would like to
support future product evolution and maintenance as well having peace of
mind knowing that our team of experts are poised to provide you with
individual technical assistance whenever you call upon them, then please
consider our Professional Subscription Support services - details can be
found on our main website.

Más información sobre la lista de distribución Seguridad