PostgreSQL 8.1.x before 8.1.4, 8.0.x before 8.0.8, 7.4.x before 7.4.13, 7.3.x before 7.3.15, and earlier versions allows context-dependent attackers to bypass SQL injection protection methods in applications that use multibyte encodings that allow the "\" (backslash) byte 0x5c to be the trailing byte of a multibyte character, such as SJIS, BIG5, GBK, GB18030, and UHC, which cannot be handled correctly by a client that does not understand multibyte encodings, aka a second variant of "Encoding-Based SQL Injection." NOTE: it could be argued that this is a class of issue related to interaction errors between the client and PostgreSQL, but a CVE has been assigned since PostgreSQL is treating this as a preventative measure against this class of problem.
https://oval.cisecurity.org/repository/search/definition/oval%3Aorg.mitre.oval%3Adef%3A9947
https://exchange.xforce.ibmcloud.com/vulnerabilities/26628
https://exchange.xforce.ibmcloud.com/vulnerabilities/26627
http://www.vupen.com/english/advisories/2006/1941
http://www.ubuntu.com/usn/usn-288-3
http://www.ubuntu.com/usn/usn-288-2
http://www.trustix.org/errata/2006/0032/
http://www.securityfocus.com/bid/18092
http://www.securityfocus.com/archive/1/435161/100/0/threaded
http://www.securityfocus.com/archive/1/435038/100/0/threaded
http://www.redhat.com/support/errata/RHSA-2006-0526.html
http://www.postgresql.org/docs/techdocs.50
http://www.novell.com/linux/security/advisories/2006_21_sr.html
http://www.mandriva.com/security/advisories?name=MDKSA-2006:098
http://www.debian.org/security/2006/dsa-1087
http://support.avaya.com/elmodocs2/security/ASA-2006-113.htm
http://securitytracker.com/id?1016142
http://security.gentoo.org/glsa/glsa-200607-04.xml
http://secunia.com/advisories/21749
http://secunia.com/advisories/21001
http://secunia.com/advisories/20782
http://secunia.com/advisories/20653
http://secunia.com/advisories/20555
http://secunia.com/advisories/20503
http://secunia.com/advisories/20451
http://secunia.com/advisories/20435
http://secunia.com/advisories/20314
http://secunia.com/advisories/20232
http://secunia.com/advisories/20231
http://lists.suse.com/archive/suse-security-announce/2006-Jun/0002.html
http://archives.postgresql.org/pgsql-announce/2006-05/msg00010.php