CVE-2026-53554

File write via crafted upload leads to code execution on SQLBot startup.

• CVSS 7.3
• 22
• Input Validation and Sanitization
• Remote

SQLBot is an intelligent Text-to-SQL system based on large language models and RAG. Prior to 1.9.0, the POST /api/v1/datasource/parseExcel endpoint in backend/apps/datasource/api/datasource.py uses attacker-controlled multipart filename data when selecting where uploaded content is stored, writes the content before spreadsheet parsing and validation finish, and can transform a double-extension filename into a Python source file. An attacker able to submit a crafted multipart upload can use these behaviors to place attacker-controlled content in /opt/sqlbot/app/alembic/versions/ even when a spreadsheet parsing failure after the file write causes the endpoint to return an error. The planted file remains on disk, and subsequent SQLBot startup or migration processing causes Alembic to import the module and execute its module-level statements in the SQLBot application runtime. This issue is fixed in version 1.9.0.

CVE

CVE-2026-53554

CWE

22

CVSS base score

7.3

Published

2026-09-17

OWASP

A08 Software and Data Integrity Failures

Orthogonal defect classification

Checking

Code defect classification

Missing Check

Category

Input Validation and Sanitization

Subcategory

Path Traversal

Accessibility scope

Remote

Impact

Arbitrary Code Execution

Affected component

SQLBot

Solution

Upgrade SQLBot to version 1.9.0 or newer.

import os
from fastapi import APIRouter, UploadFile, HTTPException

router = APIRouter()
UPLOAD_ROOT = "/opt/sqlbot/tmp/uploads"

@router.post("/api/v1/datasource/parseExcel")
async def parse_excel(file: UploadFile):
    # VULNERABLE: uses attacker-controlled filename for storage path
    dest_path = os.path.join(UPLOAD_ROOT, file.filename)
    try:
        with open(dest_path, "wb") as out_file:
            while content := await file.read(1024):
                out_file.write(content)
    except Exception as e:
        raise HTTPException(status_code=500, detail="Failed to store file")
    return {"status": "uploaded"}

import os
from fastapi import APIRouter, UploadFile, HTTPException

router = APIRouter()
UPLOAD_ROOT = "/opt/sqlbot/tmp/uploads"
ALLOWED_EXT = ".xlsx"

@router.post("/api/v1/datasource/parseExcel")
async def parse_excel(file: UploadFile):
    # FIX: sanitize filename and enforce allowed extension
    safe_name = os.path.basename(file.filename)
    if not safe_name.lower().endswith(ALLOWED_EXT):
        raise HTTPException(status_code=400, detail="Invalid file type")
    dest_path = os.path.join(UPLOAD_ROOT, safe_name)
    try:
        with open(dest_path, "wb") as out_file:
            while content := await file.read(1024):
                out_file.write(content)
    except Exception as e:
        raise HTTPException(status_code=500, detail="Failed to store file")
    return {"status": "uploaded"}

__VAITP_MODEL_REFUSED__

@misc{vaitp:cve202653554,
  title        = {{File write via crafted upload leads to code execution on SQLBot startup.}},
  author       = {Bogaerts, Fr\'ed\'eric and Ivaki, Naghmeh and Fonseca, Jos\'e},
  year         = {2026},
  note         = {VAITP Python Vulnerability Dataset, entry CVE-2026-53554},
  howpublished = {\url{https://netpack.pt/vaitp/vulnerability/CVE-2026-53554/}}
}