# CVE-2026-18447: PostgreSQL output parameter type confusion executes arbitrary code

Status: published. Published: 2026-11-12. Updated: 2026-11-12.

Type confusion in PostgreSQL SQL-language functions allows an object creator to execute arbitrary code as the operating system user running the database, via an output parameter of type "any".  Versions before PostgreSQL 18.7, 17.12, 16.16, 15.20, and 14.25 are affected.

## Remediation

No remediation reported in collected sources

## Affected products and versions

- n/a / PostgreSQL: ≥ 18; < 18.7 (affected, rpm); ≥ 17; < 17.12 (affected, rpm); ≥ 16; < 16.16 (affected, rpm); ≥ 15; < 15.20 (affected, rpm); ≥ 0; < 14.25 (affected, rpm). Source: CNA: PostgreSQL

## Severity and prioritization

- CVSS 3.1: 8.8 (high); CVSS:3.1/AV:N/AC:L/PR:L/UI:N/S:U/C:H/I:H/A:H; source: CNA: PostgreSQL

- CISA KEV: No listing in collected sources

- EPSS: Not available

- SSVC: Not available

- Weaknesses: CWE-843

## Exploit evidence

No exploit evidence in collected sources. This is not proof of no exploitation.

## References

- https://www.postgresql.org/support/security/CVE-2026-18447/ (CNA: PostgreSQL)

## Provenance

- CNA: PostgreSQL: https://www.cve.org/CVERecord?id=CVE-2026-18447; retrieved 2026-11-12; source updated 2026-11-12

Revision: 36e1bd300e1cc979b8877261f1f91c55d4e6dc94b7bd6adeda94325a0d23dec8

Canonical: https://y2.dev/cve/CVE-2026-18447

## Agent and API access

Public CVE pages, Markdown, and JSON are free to read without an account or API key.

- Public catalog: https://y2.dev/cve/index.json. Follow nextCursor with the same search, filters, sort, and limit (1–100). A null cursor marks the end.

- WebMCP: search_cve_disclosures, get_cve_disclosure, get_cve_page_markdown, get_y2_cve_access. Available in compatible browsers.

- Cyber API: https://api.y2.dev/api/v2/cyber/cves and https://api.y2.dev/api/v2/cyber/cves/{cveId}.

- Y2 Pro or Elite: create a workspace API key with the intel:cyber scope and send Authorization: Bearer <Y2_API_KEY>. Setup: https://y2.dev/docs/api/create-key.

- x402: Pay per request without an account or API key. Omit Authorization, read the HTTP 402 PAYMENT-REQUIRED challenge, validate its current requirements, and retry with PAYMENT-SIGNATURE through an authorized payment client. These browser tools never make payments. Guide: https://y2.dev/docs/api/x402.

- OpenAPI: https://y2.dev/api/openapi.yaml. Agent access metadata: https://y2.dev/cve/agent.json.

Collected public records only. Check source status for coverage and freshness.