The snprintf implementation in PostgreSQL before 9.0.20, 9.1.x before 9.1.16, 9.2.x before 9.2.11, 9.3.x before 9.3.7, and 9.4.x before 9.4.2 does not properly handle system-call errors, which allows attackers to obtain sensitive information or have other unspecified impact via unknown vectors, as demonstrated by an out-of-memory error.
http://www.postgresql.org/docs/9.4/static/release-9-4-2.html
http://www.postgresql.org/docs/9.3/static/release-9-3-7.html
http://www.postgresql.org/docs/9.2/static/release-9-2-11.html
http://www.postgresql.org/docs/9.1/static/release-9-1-16.html
http://www.postgresql.org/docs/9.0/static/release-9-0-20.html
http://www.postgresql.org/about/news/1587/
http://www.debian.org/security/2015/dsa-3270