{"id":"CVE-2026-17351","title":"The fix for CVE-2026-12045 in pgAdmin 4 9.16 required the LLM-supplied query passed to the AI Assistant's execute_sql_query tool to parse, via sqlparse, as exactly one non-transaction-control statement before running it inside a BEGIN TR…","summary":"The fix for CVE-2026-12045 in pgAdmin 4 9.16 required the LLM-supplied query passed to the AI Assistant's execute_sql_query tool to parse, via sqlparse, as exactly one non-transaction-control statement before running it inside a BEGIN TR…","severity":"critical","cvss":9,"cvssVector":"CVSS:3.1/AV:N/AC:L/PR:L/UI:R/S:C/C:H/I:H/A:H","cwe":["CWE-89","CWE-115"],"published":"2026-07-31","updated":"2026-08-01","source":"NVD","sourceUrl":"https://nvd.nist.gov/vuln/detail/CVE-2026-17351","references":[{"url":"https://github.com/pgadmin-org/pgadmin4/commit/bf4792444446f0e7ab721d23cbd6bfe6afaa7a8b","label":"f86ef6dc-4d3a-42ad-8f28-e6d5547a5007"},{"url":"https://github.com/pgadmin-org/pgadmin4/commit/ef76102bcd1cdb544eb9b4ef18d3382f22b76752","label":"f86ef6dc-4d3a-42ad-8f28-e6d5547a5007"},{"url":"https://github.com/pgadmin-org/pgadmin4/issues/10192","label":"f86ef6dc-4d3a-42ad-8f28-e6d5547a5007"}],"tags":["nvd","exploit-available"],"epss":0.00483,"epssPercentile":0.39056,"ingestedAt":"2026-08-02T00:16:16.215Z","exploits":{"github":1,"githubRepos":["https://github.com/Hunt-Benito/pgadmin-ai-assistant-sql-injection-cve-2026-17351-lexer-differential-bypass"],"checkedAt":"2026-09-26T09:05:39.004Z"},"exploitAvailable":true,"slug":"CVE-2026-17351","body":"## Overview\n\nThe fix for CVE-2026-12045 in pgAdmin 4 9.16 required the LLM-supplied query passed to the AI Assistant's execute_sql_query tool to parse, via sqlparse, as exactly one non-transaction-control statement before running it inside a BEGIN TRANSACTION READ ONLY wrapper. sqlparse's string-literal lexing can disagree with PostgreSQL's own parser: under standard_conforming_strings = on (PostgreSQL's default since 9.1), a backslash immediately before a quote is an ordinary character to PostgreSQL, but sqlparse treats it as escaping the quote. A payload such as SELECT '\\';COMMIT;CREATE TABLE pwn(x int);SELECT 1 --' therefore parses as a single SELECT to sqlparse's validator, while PostgreSQL executes it as four statements: the smuggled COMMIT ends the wrapping read-only transaction, and the trailing ROLLBACK becomes a no-op. This reintroduces the same write/RCE bypass CVE-2026-12045 was meant to close, reachable via the same indirect prompt-injection delivery (an attacker plants the payload in any object the AI Assistant may read; the LLM emits it as a tool call).\n\nAn initial candidate fix ran the query with psycopg's execute(..., prepare=True), intending to force PostgreSQL's own Parse step (extended query protocol) to reject multi-statement text regardless of sqlparse's classification. This candidate fix does not work as submitted: psycopg3's PrepareManager silently ignores the prepare argument whenever the connection's prepare_threshold is None, which is pgAdmin's default for every server connection (the per-server \"Prepare threshold\" field is blank unless an administrator explicitly sets it) -- psycopg3 falls back to the simple query protocol, the same multi-statement-capable path the bypass exploits, so the candidate fix closes nothing on any real-world default configuration.\n\nThe corrected fix sets conn.prepare_threshold = 0 directly on the dedicated, single-use read-only connection the AI Assistant tool opens, structurally forcing the extended query protocol independent of any server-level configuration. Verified against a live PostgreSQL 18 instance: the payload executes successfully under the prepare_threshold=None (default) behavior, and is rejected with \"cannot insert multiple commands into a prepared statement\" once prepare_threshold=0 is set on that connection.\n\nThis issue affects pgAdmin 4: from 9.13 before 9.17.\n\n## Remediation\n\nRefer to the linked advisories for vendor-supplied fixes and affected version ranges.","depth":"abyssal","depthScore":62,"depthScoreParts":{"impact":49.5,"likelihood":0.1,"exploitation":12,"ransomware":0},"changes":[{"seq":4975,"id":"CVE-2026-17351","ts":1788887222366,"field":"exploit_available","old":"false","new":"true"},{"seq":3858,"id":"CVE-2026-17351","ts":1788886354907,"field":"exploit_available","old":"true","new":"false"},{"seq":2686,"id":"CVE-2026-17351","ts":1788883019738,"field":"exploit_available","old":"false","new":"true"},{"seq":1715,"id":"CVE-2026-17351","ts":1788882424572,"field":"exploit_available","old":"true","new":"false"},{"seq":821,"id":"CVE-2026-17351","ts":1788881857877,"field":"exploit_available","old":"false","new":"true"}]}