CVE-2026-8838 — Amazon Redshift Python Driver RCE via Unsafe Code Execution

Executive Summary

A critical remote code execution vulnerability (CVE-2026-8838) has been disclosed in the Amazon Redshift Python driver (amazon-redshift-python-driver). Versions below 2.1.14 are affected. The vector_in() function in the driver executes arbitrary code received from the server using Python's built-in dynamic code execution capability — without any sanitization or validation of the server-provided data.

CVSS Score: 9.8 (Critical) CWE: CWE-95 — Improper Neutralization of Directives in Dynamically Evaluated Code

Any application connecting to an Amazon Redshift instance via this driver is potentially vulnerable if the connection can be intercepted (man-in-the-middle) or if the Redshift endpoint itself is compromised. Upgrade to version 2.1.14 immediately.

Vulnerability Overview

Affected Products

Technical Analysis

Root Cause

The vector_in() function in the Amazon Redshift Python driver is responsible for deserializing vector data type values returned by a Redshift server response. The implementation uses Python's dynamic code execution function to process the server-returned data string — treating the server response as executable code rather than as plain data to be parsed.

This design pattern is inherently dangerous because:

1. The server controls the input — In a MITM scenario or with a compromised server, an attacker controls exactly what string is passed to the execution function
2. No sandboxing — The execution occurs in the full Python runtime context with all available modules and capabilities
3. Client-side execution — The vulnerability affects the connecting client machine, not the server

Attack Scenarios

Scenario 1: Man-in-the-Middle (MITM)

An attacker positioned between the client application and the Redshift endpoint intercepts the TLS-encrypted connection (using a fraudulent certificate, DNS spoofing, or BGP hijacking) and injects a malicious payload in place of a legitimate server vector data response:

# Malicious server response injects arbitrary code
# instead of legitimate vector data

Scenario 2: Compromised or Rogue Server

An attacker who has compromised the Redshift endpoint — or who tricks an application into connecting to a malicious Redshift-compatible server — can return crafted responses that execute arbitrary code on any connecting client.

Scenario 3: DNS Spoofing / Endpoint Substitution

If an attacker can manipulate DNS resolution for the Redshift endpoint hostname, client applications will connect to a malicious server that exploits this vulnerability to achieve RCE on the client.

Impact Scope

The vulnerability executes code on the client machine — meaning the affected party is the application server, data pipeline, ETL job, or analytics environment that uses this driver to query Redshift. This could include:

• Production application servers with database access
• Data engineering pipelines and ETL jobs
• Jupyter notebooks and analytical environments
• AWS Lambda functions or container workloads using the driver

Impact Assessment

Immediate Remediation

Step 1: Upgrade the Driver

Upgrade amazon-redshift-python-driver to version 2.1.14 or later:

# Check current installed version
pip show amazon-redshift-python-driver
 
# Upgrade to patched version
pip install --upgrade amazon-redshift-python-driver
 
# Or pin to a specific safe version
pip install "amazon-redshift-python-driver>=2.1.14"
 
# Verify the upgrade
pip show amazon-redshift-python-driver | grep Version

For projects using requirements.txt or pyproject.toml:

# requirements.txt — update the pinned version
amazon-redshift-python-driver>=2.1.14
 
# pyproject.toml (Poetry or similar)
amazon-redshift-python-driver = ">=2.1.14"
 
# After updating, reinstall dependencies
pip install -r requirements.txt
# or
poetry update amazon-redshift-python-driver

Step 2: Verify TLS Certificate Validation

Ensure your Redshift connection configuration enforces TLS certificate validation to reduce MITM risk:

import redshift_connector
 
conn = redshift_connector.connect(
    host='your-cluster.region.redshift.amazonaws.com',
    database='dev',
    user='username',
    password='password',
    ssl=True,
    sslmode='verify-full',  # Enforce full certificate verification
)

Step 3: Use VPC Endpoints

For AWS-hosted workloads, restrict Redshift connectivity to use VPC endpoints, eliminating the MITM attack surface:

# Create a Redshift VPC endpoint if not already in place
aws ec2 create-vpc-endpoint \
  --vpc-id vpc-xxxxxxxx \
  --service-name com.amazonaws.region.redshift \
  --vpc-endpoint-type Interface \
  --subnet-ids subnet-xxxxxxxx

Step 4: Review Connection Configurations

Audit all locations where amazon-redshift-python-driver is used in your codebase:

# Find all uses of the Redshift driver
grep -r "redshift_connector\|amazon-redshift" . --include="*.py" -l
 
# Check for any connections without SSL enforcement
grep -r "ssl=False\|sslmode.*disable" . --include="*.py"

Detection Indicators

# Check for unexpected child processes from Python
ps aux | grep python
 
# Review network connections from application server
ss -tnp | grep python
 
# Check CloudWatch/CloudTrail for anomalous API calls
aws cloudtrail lookup-events \
  --lookup-attributes AttributeKey=Username,AttributeValue=your-app-role \
  --start-time $(date -d '24 hours ago' -u +%Y-%m-%dT%H:%M:%SZ)

Post-Remediation Checklist

1. Upgrade all environments (dev, staging, production) to amazon-redshift-python-driver>=2.1.14
2. Rotate AWS credentials, database passwords, and any secrets accessible from affected application environments
3. Enforce TLS certificate validation (sslmode=verify-full) on all Redshift connections
4. Restrict Redshift access to VPC endpoints where possible
5. Audit recent application logs for anomalous behaviour consistent with exploitation
6. Update dependency lockfiles (requirements.txt, Pipfile.lock, poetry.lock) and rebuild containers
7. Scan your dependency tree for other packages with similar unsafe dynamic execution patterns

References

• NVD — CVE-2026-8838
• PyPI — amazon-redshift-python-driver
• CWE-95 — Improper Neutralization of Directives in Dynamically Evaluated Code
• AWS — Amazon Redshift Security
• OWASP — Code Injection