CVE-2026-32687: Postgrex SQL Injection Vulnerability

HIGH
Advisory Identifier: GHSA-r73h-97w8-m54h
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CWE-89
Published
Advisory Summary

CVE-2026-32687 is a HIGH sql injection vulnerability (CWE-89: Improper Neutralization of Special Elements used in an SQL Command ('SQL Injection')) affecting Postgrex libraries in the Hex ecosystem. The issue involves channel-name sql injection in `postgrex.notifications.listen/3`. Remediation is available by upgrading affected packages to version 0.22.2.

CVE-2026-32687 at a Glance

CVE Identifier CVE-2026-32687
GHSA Identifier GHSA-r73h-97w8-m54h
Severity HIGH
CVSS v3.1 Base Score N/A
CWE Classification CWE-89: Improper Neutralization of Special Elements used in an SQL Command ('SQL Injection')
Affected Product Postgrex
Package Ecosystem Hex
Published Date
Last Updated

How to Fix CVE-2026-32687

To remediate this vulnerability, upgrade all affected Postgrex dependencies to a patched release. Both direct and transitive dependencies should be checked, as frameworks or security libraries may pull in vulnerable versions transitively.

postgrex fixed: 0.22.2 
Upgrade postgrex to 0.22.2
Verify Direct and Transitive Dependencies

Run the following command in your project directory to verify that all resolved dependencies use the patched release: 

inspect dependencies for postgrex

How to Check if You Are Affected

To determine whether your application is affected by CVE-2026-32687, inspect your project dependencies for Postgrex:

inspect dependencies for postgrex

Analyze the terminal output to locate any version of Postgrex in your dependency tree. If any resolved version matches the vulnerable ranges listed in the table below (for example, versions earlier than 0.22.2), your application is affected.

Note: Verify declared build manifests and deployed runtime container environments.

Technical Details

Vulnerability Mechanism & Technical Analysis

This vulnerability is classified under CWE-89: Improper Neutralization of Special Elements used in an SQL Command ('SQL Injection'), where the product constructs all or part of an sql command using externally-influenced input from an upstream component, but it does not neutralize or incorrectly neutralizes special elements that could modify the intended sql command when it is sent to a downstream component. without sufficient removal or quoting of sql syntax in user-controllable inputs, the generated sql query can cause those inputs to be interpreted as sql instead of ordinary user data. In Postgrex, software state validation or input boundaries are circumvented during processing. Review the official source advisory statement below for specific affected components, classes, and reproduction details.

Source Advisory Statement

### Summary SQL injection in `Postgrex.Notifications.listen/3`: the `channel` argument is interpolated straight into `LISTEN "..."` / `UNLISTEN "..."` without escaping the `"` character. Any caller that lets a user influence the channel name (e.g. a pub/sub bridge that uses a tenant id or topic slug as the channel) and the name is not sanitized can execute arbitrary SQL on the notifications connection. Only those using the `Postgrex.Notifications` directly or via a dependency, with a non-sanitized channel name are vulnerable. Ecto does not use Postgrex.Notifications by default, but you must validate if any other dependency does. ### Details PostgreSQL escapes a `"` inside a quoted identifier by doubling it to `""`. Postgrex doesn't do that doubling, so a `"` inside `channel` closes the identifier early and everything after it is parsed as SQL on the same connection. The notifications connection runs as whatever DB role the app is configured with. Unlike the `Postgrex.query/4` API, there's no extended-protocol guard here: `LISTEN`/`UNLISTEN` are sent as simple queries, so multi-statement payloads work and the attacker can chain `; CREATE TABLE …`, `; DROP …`, `; CREATE ROLE …`, etc. ### Impact SQL injection on the notifications connection. Affects any application that calls `Postgrex.Notifications.listen/3` (or `unlisten/3`) with a channel name derived from untrusted input. Executes as the configured DB user with no protocol-level limit on what can be chained, so the realistic blast radius is read/modify/destroy on any data the app's DB role can reach. ### Fix Upgrade to latest Postgrex v0.22.2 or later. Altenratively, sanitize any user input given as channel name by making sure it doesn't include quotes as well as null bytes (not strictly required, but recommended): ```elixir if String.contains?(channel_name, ["\"", "\0"]) do raise "bad channel name" end ```

CVE-2026-32687 Affected Postgrex Versions

1 component(s)
Fixed Versions:
0.22.2
Product / Package Ecosystem Affected Versions Fixed Version
postgrex
 Hex
≥ 0.16.0
< 0.22.2
0.22.2

References

GitHub Advisory / Wiki ADVISORY
https://github.com/elixir-ecto/ecto/security/advisories/GHSA-r73h-97w8-m54h
NVD — CVE-2026-32687 NVD
https://nvd.nist.gov/vuln/detail/CVE-2026-32687
Security Fix Commit FIX COMMIT
https://github.com/elixir-ecto/postgrex/commit/7cdedbd4316bb65f82e6a9a4f922c0ac491cb770
cna.erlef.org/cves/cve-2026-32687... WEB
https://cna.erlef.org/cves/CVE-2026-32687.html
Postgrex Source Repository REPOSITORY
https://github.com/elixir-ecto/ecto
osv.dev/vulnerability/eef-c... WEB
https://osv.dev/vulnerability/EEF-CVE-2026-32687

Frequently Asked Questions

What is CVE-2026-32687?
CVE-2026-32687 is a security vulnerability in Postgrex involving Channel-name SQL injection in `Postgrex.Notifications.listen/3` under CWE-89: Improper Neutralization of Special Elements used in an SQL Command ('SQL Injection').
Which Postgrex versions are affected?
Affected versions include releases prior to 0.22.2 across affected packages: postgrex.
What version fixes CVE-2026-32687?
Upgrading to 0.22.2 (or the latest patched release for your respective branch) resolves the vulnerability.
Is postgrex affected?
Yes, postgrex is affected in releases prior to 0.22.2. Upgrade your dependency to 0.22.2 or later.
What CWE is associated with CVE-2026-32687?
CVE-2026-32687 is classified under CWE-89: Improper Neutralization of Special Elements used in an SQL Command ('SQL Injection') (The product constructs all or part of an SQL command using externally-influenced input from an upstream component, but it does not neutralize or incorrectly neutralizes special elements that could modify the intended SQL command when it is sent to a downstream component. Without sufficient removal or quoting of SQL syntax in user-controllable inputs, the generated SQL query can cause those inputs to be interpreted as SQL instead of ordinary user data.).
How can I check Hex dependencies for CVE-2026-32687?
Run the dependency tree command: 'inspect dependencies for postgrex'. This command lists direct and transitive dependencies in your build configuration so you can verify if a vulnerable version is resolved.
Machine-readable OSV JSON OSV v1.5 Schema
Normalized schema output
View Raw JSON 
{
  "schema_version" : "1.4.0",
  "id" : "GHSA-r73h-97w8-m54h",
  "modified" : "2026-05-18T17:53:17Z",
  "published" : "2026-05-18T17:53:17Z",
  "aliases" : [ "CVE-2026-32687" ],
  "summary" : "Postgrex: Channel-name SQL injection in `Postgrex.Notifications.listen/3`",
  "details" : "### Summary\n\nSQL injection in `Postgrex.Notifications.listen/3`: the `channel` argument is interpolated straight into `LISTEN \"...\"` / `UNLISTEN \"...\"` without escaping the `\"` character. Any caller that lets a user influence the channel name (e.g. a pub/sub bridge that uses a tenant id or topic slug as the channel) and the name is not sanitized can execute arbitrary SQL on the notifications connection.\n\nOnly those using the `Postgrex.Notifications` directly or via a dependency, with a non-sanitized channel name are vulnerable. Ecto does not use Postgrex.Notifications by default, but you must validate if any other dependency does.\n\n### Details\n\nPostgreSQL escapes a `\"` inside a quoted identifier by doubling it to `\"\"`. Postgrex doesn't do that doubling, so a `\"` inside `channel` closes the identifier early and everything after it is parsed as SQL on the same connection.\n\nThe notifications connection runs as whatever DB role the app is configured with. Unlike the `Postgrex.query/4` API, there's no extended-protocol guard here: `LISTEN`/`UNLISTEN` are sent as simple queries, so multi-statement payloads work and the attacker can chain `; CREATE TABLE …`, `; DROP …`, `; CREATE ROLE …`, etc.\n\n### Impact\n\nSQL injection on the notifications connection. Affects any application that calls `Postgrex.Notifications.listen/3` (or `unlisten/3`) with a channel name derived from untrusted input. Executes as the configured DB user with no protocol-level limit on what can be chained, so the realistic blast radius is read/modify/destroy on any data the app's DB role can reach.\n\n### Fix\n\nUpgrade to latest Postgrex v0.22.2 or later. Altenratively, sanitize any user input given as channel name by making sure it doesn't include quotes as well as null bytes (not strictly required, but recommended):\n\n```elixir\nif String.contains?(channel_name, [\"\\\"\", \"\\0\"]) do\n  raise \"bad channel name\"\nend\n```",
  "severity" : [ {
    "type" : "CVSS_V4",
    "score" : "CVSS:4.0/AV:L/AC:L/AT:P/PR:N/UI:N/VC:H/VI:H/VA:H/SC:N/SI:N/SA:N"
  } ],
  "affected" : [ {
    "package" : {
      "ecosystem" : "Hex",
      "name" : "postgrex"
    },
    "ranges" : [ {
      "type" : "ECOSYSTEM",
      "events" : [ {
        "introduced" : "0.16.0"
      }, {
        "fixed" : "0.22.2"
      } ]
    } ]
  } ],
  "references" : [ {
    "type" : "WEB",
    "url" : "https://github.com/elixir-ecto/ecto/security/advisories/GHSA-r73h-97w8-m54h"
  }, {
    "type" : "ADVISORY",
    "url" : "https://nvd.nist.gov/vuln/detail/CVE-2026-32687"
  }, {
    "type" : "WEB",
    "url" : "https://github.com/elixir-ecto/postgrex/commit/7cdedbd4316bb65f82e6a9a4f922c0ac491cb770"
  }, {
    "type" : "WEB",
    "url" : "https://cna.erlef.org/cves/CVE-2026-32687.html"
  }, {
    "type" : "PACKAGE",
    "url" : "https://github.com/elixir-ecto/ecto"
  }, {
    "type" : "WEB",
    "url" : "https://osv.dev/vulnerability/EEF-CVE-2026-32687"
  } ],
  "database_specific" : {
    "cwe_ids" : [ "CWE-89" ],
    "severity" : "HIGH",
    "github_reviewed" : true,
    "github_reviewed_at" : "2026-05-18T17:53:17Z",
    "nvd_published_at" : "2026-05-12T15:16:12Z"
  }
}