Updated postgresql packages that fix one security issue are now available for Red Hat Enterprise Linux 4, 5, and 6.
The Red Hat Security Response Team has rated this update as having moderate security impact. A Common Vulnerability Scoring System (CVSS) base score, which gives a detailed severity rating, is available from the CVE link associated with the description below.
PostgreSQL is an advanced object-relational database management system (DBMS).
A signedness issue was found in the way the crypt() function in the PostgreSQL pgcrypto module handled 8-bit characters in passwords when using Blowfish hashing. Up to three characters immediately preceding a non-ASCII character (one with the high bit set) had no effect on the hash result, thus shortening the effective password length. This made brute-force guessing more efficient as several different passwords were hashed to the same value.
Due to the CVE-2011-2483
fix, after installing this update some users may not be able to log in to applications that store user passwords, hashed with Blowfish using the PostgreSQL crypt() function, in a back-end PostgreSQL database. Unsafe processing can be re-enabled for specific passwords (allowing affected users to log in) by changing their hash prefix to "$2x$".
For Red Hat Enterprise Linux 6, the updated postgresql packages upgrade PostgreSQL to version 8.4.9. Refer to the PostgreSQL Release Notes for a full list of changes:
For Red Hat Enterprise Linux 4 and 5, the updated postgresql packages contain a backported patch.
All PostgreSQL users are advised to upgrade to these updated packages, which correct this issue. If the postgresql service is running, it will be automatically restarted after installing this update.
Updated postgresql packages that fix one bug are now available for Red Hat Enterprise Linux 5.
PostgreSQL is an advanced Object-Relational database management system (DBMS). The base postgresql package includes client programs and libraries that are needed to access a PostgreSQL DBMS server.
The client library for PostgreSQL, libpq, sets up OpenSSL callback functions when using an SSL-encrypted connection to the database server. These callbacks were not unregistered when the connection to the database was closed. If the calling application unloaded the libpq library after closing the connection, any subsequent attempt to use OpenSSL failed with a segmentation fault. To fix this problem, OpenSSL callbacks are now unregistered whenever the last active database connection is closed so that the library can be unloaded safely. OpenSSL Segmentation faults no longer occur in the scenario described.
All users of postgresql are advised to upgrade to these updated packages, which fix this bug.