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Security Bulletin: IBM i is affected by networking BIND vulnerability CVE-2018-5743

Security Bulletin


ISC BIND is vulnerable to this security vulnerability. IBM i has addressed this vulnerability.

Vulnerability Details

CVEID: CVE-2018-5743
DESCRIPTION: ISC BIND is vulnerable to a denial of service, caused by a flaw when setting the TCP client quota using the tcp-clients option. By sending a specially-crafted request, a remote attacker could exploit this vulnerability to cause the exhaustion of file descriptors.
CVSS Base Score: 7.5
CVSS Temporal Score: See 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 7.1, 7.2, 7.3, and 7.4 of IBM i are affected.


The issue can be fixed by applying a PTF to IBM i.
Releases 7.1, 7.2, 7.3, and 7.4 of IBM i are supported and will be fixed.

The IBM i PTF numbers are:
Release 7.1 – SI69882
Release 7.2 – SI69883
Release 7.3 – SI69885
Release 7.4 – SI69886

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


Get Notified about Future Security Bulletins


Complete CVSS v3 Guide
On-line Calculator v3

Related Information

IBM Secure Engineering Web Portal
IBM Product Security Incident Response Blog

Change History

17 June 2019: Original Version Published

*The CVSS Environment Score is customer environment specific and will ultimately impact the Overall CVSS Score. Customers can evaluate the impact of this vulnerability in their environments by accessing the links in the Reference section of this Security Bulletin.


According to the Forum of Incident Response and Security Teams (FIRST), the Common Vulnerability Scoring System (CVSS) is an "industry open standard designed to convey vulnerability severity and help to determine urgency and priority of response." IBM PROVIDES THE CVSS SCORES ""AS IS"" WITHOUT WARRANTY OF ANY KIND, INCLUDING THE IMPLIED WARRANTIES OF MERCHANTABILITY AND FITNESS FOR A PARTICULAR PURPOSE. CUSTOMERS ARE RESPONSIBLE FOR ASSESSING THE IMPACT OF ANY ACTUAL OR POTENTIAL SECURITY VULNERABILITY.

Cross reference information
Product Component Platform Version Edition
IBM i 7.1 IBM i 7.1
IBM i 7.2 IBM i 7.2
IBM i 7.3 IBM i 7.3
IBM i 7.4 IBM i 7.4

Document information

More support for: IBM i

Software version: 7.1,7.2,7.3,7.4

Operating system(s): IBM i

Reference #: 0883384

Modified date: 17 June 2019