Drupal core "highly critical" pre-patch warning, unauthenticated, zero-complexity, patch window today 17:00–21:00 UTC

Yesterday's brief carried Drupal's PSA pre-warning that a "highly critical" core advisory was scheduled for 2026-05-20; today the SA-CORE-2026-004 advisory landed with CVE-2026-9082 assigned, an anonymous SQL-injection in Drupal core's database abstraction API (CWE-89) rated 20/25 on Drupal's risk scale (Highly Critical) that affects only PostgreSQL-backed installations. Specially-crafted HTTP requests slip past sanitisation in the core DB-API layer and inject arbitrary SQL with no authentication; successful exploitation leads to information disclosure, privilege escalation and (in some database configurations) RCE. The Drupal Security Team explicitly stated that "exploits might be developed within hours or days" of advisory release (Drupal PSA, 2026-05-18).

Affected versions: 8.9.0 through 10.4.10, 10.5.x < 10.5.10, 10.6.x < 10.6.9, 11.0.0 through 11.1.10, 11.2.x < 11.2.12, 11.3.x < 11.3.10. Patched: 10.4.10 / 10.5.10 / 10.6.9 / 11.1.10 / 11.2.12 / 11.3.10 (released 2026-05-20). MySQL / MariaDB / SQLite installations are not affected by this CVE. Drupal 7 is unaffected; sites on EOL Drupal 8/9 majors must apply manual patch files. Drupal Steward WAF subscribers receive vendor-provided rules at advisory release per the service description; non-subscriber sites must apply the core update. NCSC-CH carried the advisory in its Security Hub (NCSC-CH, 2026-05-19; SecurityWeek, 2026-05-19; CSO Online, 2026-05-20).

On 2026-05-22 Drupal updated SA-CORE-2026-004 to confirm that exploit attempts targeting CVE-2026-9082 (the anonymous pre-authentication SQL injection in the Entity Query API's PostgreSQL path) are now being detected in the wild. NCSC.ch updated Security Hub post 12584 to "Actively exploited" status the same day at 13:52Z, also recording the addition of CVE-2026-9082 to the CISA Known Exploited Vulnerabilities catalog on 2026-05-22 (the NCSC-CH post is the brief's source of record on the KEV add; the CISA news-events alert URL constructed earlier in the day returned a 404 at composition time).

Imperva reports observing 15,000+ exploitation attempts against approximately 6,000 Drupal sites across 65 countries within days of disclosure (Imperva, 2026-05-21). The technical mechanism (now public via the Searchlight Cyber write-up): on the case-insensitive IN operator path through core/lib/Drupal/Core/Entity/Query/Sql/Condition::compile() / ConditionAggregate::compile(), a JSON-encoded array value survives into the SQL placeholder name without sanitisation, allowing injection when the backend is PostgreSQL. Fixed versions: 10.4.10, 10.5.10, 10.6.9, 11.1.10, 11.2.12 and 11.3.10; best-effort patches for EOL Drupal 8.9 and 9 are also available. MySQL/MariaDB/SQLite-backed Drupal sites remain unaffected, which is the temporary control to fall back on if the patch window slips past today.

Defender vantage update from yesterday's brief: the operational frame is no longer "patch when convenient" but patch today; the § 0 Immediate Action carries the operational framing; this UPDATE captures the source-of-record links and the technical mechanism for anyone composing internal advisories or hunt queries. CH/EU specifics: NCSC.ch Security Hub is the authoritative jurisdictional source for Swiss federal and cantonal operators; Drupal-on-PostgreSQL is widespread across FITKO and SWITCH-hosted university sites, French gouvernement.fr instances and EU institution portals. Detection: WAF telemetry for nested JSON arrays in user-supplied fields hitting Drupal endpoints; PostgreSQL log_min_duration_statement to surface anomalous query shapes; web-server logs for unexpected POST payloads to anonymous routes.