CVE-2026-41496: PraisonAI: SQL Injection via unvalidated `table_prefix` in 9 conversation store backends (incomplete fix for )

Executive brief

The fix for [CVE-2026-40315](https://github.com/MervinPraison/PraisonAI/security/advisories/GHSA-x783-xp3g-mqhp) added input validation to `SQLiteConversationStore` only. Nine sibling backends — MySQL, PostgreSQL, async SQLite/MySQL/PostgreSQL, Turso, SingleStore, Supabase, SurrealDB — pass `table_prefix` straight into f-string SQL. Same root cause, same code pattern, same exploitation. 52 unvalidated injection points across the codebase.

`postgres.py` additionally accepts an unvalidated `schema` parameter used directly in DDL.

### Severity

**High** — CWE-89 (SQL Injection)

CVSS:3.1/AV:N/AC:L/PR:L/UI:N/S:U/C:H/I:H/A:N — **8.1**

Exploitable in any deployment where `table_prefix` is derived from external input (multi-tenant setups, API-driven configuration, user-modifiable config files). Default config (`"praison_"`) is not affected.

### Details

The [CVE-2026-40315 fix](https://github.com/MervinPraison/PraisonAI/security/advisories/GHSA-x783-xp3g-mqhp) added this guard to `sqlite.py:52`:

```python # sqlite.py — PATCHED import re if not re.match(r'^[a-zA-Z0-9_]* , table_prefix): raise ValueError("table_prefix must contain only alphanumeric characters and underscores") ```

The following backends perform the identical `table_prefix → f-string SQL` pattern **without this guard**:

| Backend | File | Line | Injection points | | ---------------- | -------------------------------------------- | --------------- | ----------------------- | | MySQL | `persistence/conversation/mysql.py` | 65 | 5 | | PostgreSQL | `persistence/conversation/postgres.py` | 89 (+schema:88) | 10 | | Async SQLite | `persistence/conversation/async_sqlite.py` | 43 | 13 | | Async MySQL | `persistence/conversation/async_mysql.py` | 65 | 13 | | Async PostgreSQL | `persistence/conversation/async_postgres.py` | 63 | 13 | | Turso/LibSQL | `persistence/conversation/turso.py` | 66 | 9 | | SingleStore | `persistence/conversation/singlestore.py` | 51 | 7 | | Supabase | `persistence/conversation/supabase.py` | 68 | 9 | | SurrealDB | `persistence/conversation/surrealdb.py` | 57 | 8 | | **Total** | **9 backends** | | **52 injection points** |

Additionally, `praisonai-agents/praisonaiagents/storage/backends.py:179` (`SQLiteBackend`) accepts `table_name` without validation.

### PoC

```python #!/usr/bin/env python3 """ Demonstrates: sqlite.py rejects malicious table_prefix, mysql.py accepts it. Run: python3 poc.py (no dependencies required) """ import re

payload = "x'; DROP TABLE users; --"

# ── SQLite (patched) ──────────────────────────────────────────────── try: if not re.match(r'^[a-zA-Z0-9_]* , payload): raise ValueError("blocked") print(f"[SQLite] FAIL — accepted: {payload}") except ValueError: print(f"[SQLite] OK — rejected malicious table_prefix")

# ── MySQL (unpatched) ─────────────────────────────────────────────── sessions_table = f"{payload}sessions" sql = f"CREATE TABLE IF NOT EXISTS {sessions_table} (session_id VARCHAR(255) PRIMARY KEY)" print(f"[MySQL] VULN — generated SQL:\n {sql}")

# ── PostgreSQL (unpatched — both table_prefix AND schema) ────────── schema = "public; DROP SCHEMA data CASCADE; --" sessions_table = f"{schema}.praison_sessions" sql = f"CREATE SCHEMA IF NOT EXISTS {schema}" print(f"[Postgres] VULN — schema injection:\n {sql}") ```

Output:

``` [SQLite] OK — rejected malicious table_prefix [MySQL] VULN — generated SQL: CREATE TABLE IF NOT EXISTS x'; DROP TABLE users; --sessions (session_id VARCHAR(255) PRIMARY KEY) [Postgres] VULN — schema injection: CREATE SCHEMA IF NOT EXISTS public; DROP SCHEMA data CASCADE; -- ```

### Vulnerable code (mysql.py, representative)

```python # mysql.py:65-67 — NO validation self.table_prefix = table_prefix # ← raw input self.sessions_table = f"{table_prefix}sessions" # ← into identifier self.messages_table = f"{table_prefix}messages"

# mysql.py:105 — straight into DDL cur.execute(f""" CREATE TABLE IF NOT EXISTS {self.sessions_table} ( session_id VARCHAR(255) PRIMARY KEY, ... ) """) ```

Compare with the patched `sqlite.py:52`:

```python # sqlite.py:52-53 — HAS validation if not re.match(r'^[a-zA-Z0-9_]* , table_prefix): raise ValueError("table_prefix must contain only alphanumeric characters and underscores") ```

### Impact

When `table_prefix` originates from untrusted input — multi-tenant tenant names, API request parameters, user-editable config — an attacker achieves **arbitrary SQL execution** against the backing database. The injected SQL runs in the context of DDL and DML operations (CREATE TABLE, INSERT, SELECT, DELETE), giving the attacker read/write/delete access to the entire database.

PostgreSQL's `schema` parameter adds a second injection vector in DDL (`CREATE SCHEMA IF NOT EXISTS {schema}`).

Affected products

• PyPI praisonaiagents
• PyPI praisonai

References

• https://api.github.com/users/BerSecHub
• https://github.com/BerSecHub
• https://api.github.com/users/BerSecHub/gists%7B/gist_id%7D
• https://api.github.com/users/BerSecHub/repos
• https://avatars.githubusercontent.com/u/134146860?v=4
• https://api.github.com/users/BerSecHub/events%7B/privacy%7D