CVE-2026-12047HTML injection in pgAdmin 4's cloud deployment module.

HTML injection in pgAdmin 4's cloud deployment module. The verify_credentials, deploy, regions, and update-server endpoints under /rds/, /azure/, /google/, and the top-level /cloud/ blueprint propagated AWS / Azure / Google SDK exception text — and the related file-resolution and database-commit exception text — into the JSON response body (the info and errormsg fields) without HTML-encoding. The Cloud Wizard frontend rendered these strings through html-react-parser, so an attacker-influenced exception message embedded structural HTML directly into the wizard's DOM. The reported entry point is /rds/verify_credentials/. An authenticated pgAdmin user submits a crafted access_key whose value contains an <iframe/src=...> payload; AWS STS rejects the credential with an IncompleteSignature exception whose text quotes the access_key verbatim; the pgAdmin backend forwards that text into the JSON info field; the Cloud Wizard's FormFooterMessage parses it as HTML. The browser fetches the iframe's src from an attacker-controlled host, and JavaScript executing inside the cross-origin iframe writes to parent.location, redirecting the victim's pgAdmin tab. Because the injection renders inside pgAdmin's own interface, X-Frame-Options and Content-Security-Policy frame-ancestors do not mitigate it. Baseline impact is self-targeted (the same user who supplied the payload sees the injection); escalation against other authenticated users requires an additional cross-site request-forgery primitive capable of submitting the malformed credential request with a valid X-pgA-CSRFToken in the victim's browser context. The same unsanitised-error-into-JSON pattern was present across multiple sibling endpoints — Azure's check_cluster_name_availability, every Google endpoint that surfaces SDK errors (verification_ack, projects, regions, instance_types, database_versions, the verify_credentials path-resolution branches), the central /deploy endpoint that bubbles str(e) from deploy_on_rds / deploy_on_azure / deploy_on_google, and update_cloud_server which surfaces the str(e) from a failing db.session.commit — all of which are now covered. Fix HTML-escapes every external/SDK exception string at the endpoint sink via a new shared sanitize_external_text helper (HTML escape with control-character strip), promoted out of the psycopg3 driver into web/pgadmin/utils/text_sanitize.py. The Cloud Wizard frontend additionally renders its FormFooterMessage in plain-text mode for backend-derived strings, so the value is never parsed as HTML even if a future sink forgets the escape. This issue affects pgAdmin 4: from 6.6 before 9.16.

CVSS

5.4 MEDIUM (v3.1, NVD)CVSS:3.1/AV:N/AC:L/PR:L/UI:R/S:C/C:L/I:L/A:N

Weakness (CWE)

CWE-79, CWE-116

Known exploited

Not in CISA's KEV catalog

EPSS (exploitation in the next 30 days)

Not loaded for this CVE

Assigned by

Not given

NVD analysis

Analyzed

Record last updated

Jun 29, 2026

First seen by InfoSec Signals

Oct 9, 2026

The CVE record on cve.org · NVD's entry

The CVE record is authoritative. Products marked “from the name” were identified from the CNA's free-text names, not a CPE, and are matched less certainly. This product uses the NVD API but is not endorsed or certified by the NVD.