Sourced from github.com/jackc/pgx/v5's changelog.

5.9.2 (April 18, 2026)

Fix SQL Injection via placeholder confusion with dollar quoted string literals (GHSA-j88v-2chj-qfwx)

SQL injection can occur when:

1. The non-default simple protocol is used.
2. A dollar quoted string literal is used in the SQL query.
3. That query contains text that would be would be interpreted outside as a placeholder outside of a string literal.
4. The value of that placeholder is controllable by the attacker.

e.g.

attackValue := `$tag$; drop table canary; --`
_, err = tx.Exec(ctx, `select $tag$ $1 $tag$, $1`, pgx.QueryExecModeSimpleProtocol, attackValue)

This is unlikely to occur outside of a contrived scenario.

5.9.1 (March 22, 2026)

• Fix: batch result format corruption when using cached prepared statements (reported by Dirkjan Bussink)

5.9.0 (March 21, 2026)

This release includes a number of new features such as SCRAM-SHA-256-PLUS support, OAuth authentication support, and PostgreSQL protocol 3.2 support.

It significantly reduces the amount of network traffic when using prepared statements (which are used automatically by default) by avoiding unnecessary Describe Portal messages. This also reduces local memory usage.

It also includes multiple fixes for potential DoS due to panic or OOM if connected to a malicious server that sends deliberately malformed messages.

• Require Go 1.25+
• Add SCRAM-SHA-256-PLUS support (Adam Brightwell)
• Add OAuth authentication support for PostgreSQL 18 (David Schneider)
• Add PostgreSQL protocol 3.2 support (Dirkjan Bussink)
• Add tsvector type support (Adam Brightwell)
• Skip Describe Portal for cached prepared statements reducing network round trips
• Make LoadTypes query easier to support on "postgres-like" servers (Jelte Fennema-Nio)
• Default empty user to current OS user matching libpq behavior (ShivangSrivastava)
• Optimize LRU statement cache with custom linked list and node pooling (Mathias Bogaert)
• Optimize date scanning by replacing regex with manual parsing (Mathias Bogaert)
• Optimize pgio append/set functions with direct byte shifts (Mathias Bogaert)
• Make RowsAffected faster (Abhishek Chanda)
• Fix: Pipeline.Close panic when server sends multiple FATAL errors (Varun Chawla)
• Fix: ContextWatcher goroutine leak (Hank Donnay)
• Fix: stdlib discard connections with open transactions in ResetSession (Jeremy Schneider)

... (truncated)

• 0aeabbc Release v5.9.2
• 60644f8 Fix SQL sanitizer bugs with dollar-quoted strings and placeholder overflow
• a5680bc Merge pull request #2531 from dolmen-go/godoc-add-links
• e34e452 doc: Add godoc links
• 08c9bb1 Fix Stringer types encoded as text instead of numeric value in composite fields
• 96b4dbd Remove unstable test
• acf88e0 Merge pull request #2526 from abrightwell/abrightwell-min-proto
• 2f81f1f Update max_protocol_version and min_protocol_version defaults
• 4e4eaed Release v5.9.1
• 6273188 Fix batch result format corruption when using cached prepared statements
• Additional commits viewable in compare view