Security Bulletin: IBM i is affected by networking BIND vulnerabilities (CVE-2016-2775, CVE-2016-2776, CVE-2016-8864 and CVE-2016-6170)

Summary

ISC BIND is vulnerable to several security vulnerabilities. IBM i has addressed these vulnerabilities.

Vulnerability Details

CVEID: CVE-2016-2775 DESCRIPTION: ISC BIND is vulnerable to a denial of service, caused by an error when lwresd or the named lwres option is enabled. By sending an overly long request, a remote attacker could exploit this vulnerability to cause the daemon to crash.
CVSS Base Score: 7.5
CVSS Temporal Score: See https://exchange.xforce.ibmcloud.com/vulnerabilities/115477 for the current score
CVSS Environmental Score*: Undefined
CVSS Vector: (CVSS:3.0/AV:N/AC:L/PR:N/UI:N/S:U/C:N/I:N/A:H)

CVEID: CVE-2016-2776 DESCRIPTION: ISC BIND is vulnerable to a denial of service, caused by an assertion failure in buffer.c while a nameserver is building responses to a specifically constructed request. By sending a specially crafted DNS packet, a remote attacker could exploit this vulnerability to make named exit unexpectedly with an assertion failure.
CVSS Base Score: 7.5
CVSS Temporal Score: See https://exchange.xforce.ibmcloud.com/vulnerabilities/117246 for the current score
CVSS Environmental Score*: Undefined
CVSS Vector: (CVSS:3.0/AV:N/AC:L/PR:N/UI:N/S:U/C:N/I:N/A:H)

CVEID: CVE-2016-6170 DESCRIPTION: ISC BIND is vulnerable to a denial of service. By sending an overly large AXFR and IXFR response, a remote authenticated attacker could exploit this vulnerability to cause a primary and secondary DNS server crash.
CVSS Base Score: 6.5
CVSS Temporal Score: See https://exchange.xforce.ibmcloud.com/vulnerabilities/114759 for the current score
CVSS Environmental Score*: Undefined
CVSS Vector: (CVSS:3.0/AV:N/AC:L/PR:L/UI:N/S:U/C:N/I:N/A:H)

CVEID: CVE-2016-8864 DESCRIPTION: ISC BIND is vulnerable to a denial of service, caused by the improper handling of responses containing a DNAME answer in db.c or resolver.c. By sending a recursive response, a remote attacker could exploit this vulnerability to trigger an assertion failure.
CVSS Base Score: 7.5
CVSS Temporal Score: See https://exchange.xforce.ibmcloud.com/vulnerabilities/118526 for the current score
CVSS Environmental Score*: Undefined
CVSS Vector: (CVSS:3.0/AV:N/AC:L/PR:N/UI:N/S:U/C:N/I:N/A:H)

Affected Products and Versions

Releases 6.1, 7.1, 7.2 and 7.3 of IBM i are affected.

Remediation/Fixes

The issue can be fixed by applying a PTF to IBM i.

Releases 6.1, 7.1, 7.2 and 7.3 of IBM i are supported and will be fixed.

http://www-933.ibm.com/support/fixcentral/

The IBM i PTF numbers are:

Release 6.1 – SI63081 Release 7.1 – SI62977 Release 7.2 – SI62942 Release 7.3 – SI62945

_Important note: _IBM recommends that all users running unsupported versions of affected products upgrade to supported and fixed version of affected products.

Workarounds and Mitigations

None known