Auth bypass in Crystaldba Postgres-Mcp
CVE-2026-85620
Postgres MCP Pro 0.3.0 contains a restricted-mode bypass vulnerability where function-name validation is not applied to RangeFunction nodes in FROM clauses. Attackers can execute file-reading functions like pg_read_file through FROM-clause syntax to read arbitrary files despite restricted-mode protections.
Vulnerability class: Broken Access Control
Published · last modified .
CVSS v3 metric
CVSS v3 base score 8.6 (High). Vector: CVSS:3.1/AV:N/AC:L/PR:N/UI:N/S:C/C:H/I:N/A:N.
EPSS exploit prediction
EPSS: 0.005 (41.9th percentile), scored .
Very low probability of exploitation in the next 30 days; routine patching cadence is appropriate. 42nd percentile — 41.9% of CVEs in the catalogue have a lower EPSS than this one. How to read EPSS.
EPSS over last 30 days · oldest: 0.004 · newest: 0.005 · change: +0.001
Affected products
Weakness classification (CWE)
References
- github.com/crystaldba/postgres-mcp (product)
- github.com/crystaldba/postgres-mcp/blob/v0.3.0/src/postgres_mcp/sql/safe_sql.py (technical-description)
- github.com/crystaldba/postgres-mcp/issues/178 (issue-tracking)
- www.vulncheck.com/advisories/postgres-mcp-pro-0.3.0-restricted-mode-bypass-via-… (third-party-advisory)
Frequently asked questions
- What is CVE-2026-85620?
- CVE-2026-85620 is a high-severity vulnerability in Crystaldba Postgres-Mcp, classified under Incorrect Authorization. CVSS score: 8.6/10. Published 2026-09-04.
- How severe is CVE-2026-85620?
- High severity. CVSS v3 base score is 8.6 out of 10.