A corrupted string could cause code that iterates with pg_mblen() to overrun its buffer. Fix, by converting all callers to one of the following: 1. Callers with a null-terminated string now use pg_mblen_cstr(), which raises an "illegal byte sequence" error if it finds a terminator in the middle of the sequence. 2. Callers with a length or end pointer now use either pg_mblen_with_len() or pg_mblen_range(), for the same effect, depending on which of the two seems more convenient at each site. 3. A small number of cases pre-validate a string, and can use pg_mblen_unbounded(). The traditional pg_mblen() function and COPYCHAR macro still exist for backward compatibility, but are no longer used by core code and are hereby deprecated. The same applies to the t_isXXX() functions. Security: CVE-2026-2006 Backpatch-through: 14 Co-authored-by: Thomas Munro <thomas.munro@gmail.com> Co-authored-by: Noah Misch <noah@leadboat.com> Reviewed-by: Heikki Linnakangas <hlinnaka@iki.fi> Reported-by: Paul Gerste (as part of zeroday.cloud) Reported-by: Moritz Sanft (as part of zeroday.cloud)
PostgreSQL Database Management System
This directory contains the source code distribution of the PostgreSQL database management system.
PostgreSQL is an advanced object-relational database management system that supports an extended subset of the SQL standard, including transactions, foreign keys, subqueries, triggers, user-defined types and functions. This distribution also contains C language bindings.
Copyright and license information can be found in the file COPYRIGHT.
General documentation about this version of PostgreSQL can be found at https://www.postgresql.org/docs/18/. In particular, information about building PostgreSQL from the source code can be found at https://www.postgresql.org/docs/18/installation.html.
The latest version of this software, and related software, may be obtained at https://www.postgresql.org/download/. For more information look at our web site located at https://www.postgresql.org/.