A crafted query that includes user-controlled portions of a dynamic filter or join in Payload’s SQLite or Postgres adapters can execute arbitrary SQL commands. This allows an attacker to read, modify or delete database contents, potentially compromising confidentiality, integrity, or availability of all content managed by the CMS and exposing sensitive data to the attacker.

All Payload instances using the open source headless CMS between release 3.0.0 (exclusive) and 3.88.0 (inclusive) and all canary releases prior to 4.0.0‑canary.27 are vulnerable. The issue is resolved in Payload v3.88.0 and the 4.0.0‑canary.27 release.

The CVSS score of 9.8 classifies this as a critical flaw and, although the EPSS score is not available, the missing KEV status indicates that the vulnerability has not yet been widely exploited. The attack vector is inferred to be through the CMS API that accepts dynamic filters or join clauses, enabling unauthenticated or otherwise untrusted users to inject malicious SQL into backend queries. Given the severity, the likelihood of exploitation remains high, particularly for exposed or publicly reachable instances.