CVE-2026-9082: Drupal Core SQL Injection — CISA KEV Alert and Defensive Response

On May 22, 2026, the Cybersecurity and Infrastructure Security Agency (CISA) added CVE-2026-9082, a critical SQL Injection vulnerability affecting Drupal Core, to its Known Exploited Vulnerabilities (KEV) Catalog. This addition is based on actionable intelligence confirming active exploitation in the wild.

Under Binding Operational Directive (BOD) 22-01, Federal Civilian Executive Branch (FCEB) agencies are required to remediate this vulnerability by the mandated due date. However, the implications extend far beyond the federal enterprise. Drupal powers a significant portion of the web, including high-profile publishing platforms, government sites, and corporate intranets.

For defenders, this is not a theoretical risk. The presence of a SQL Injection (SQLi) flaw in Core—the heart of the CMS—means attackers can bypass authentication, access sensitive data, or potentially achieve Remote Code Execution (RCE) depending on database configuration. This post provides the technical context, detection logic, and remediation steps necessary to secure your environment against this active threat.

Technical Analysis

Vulnerability: CVE-2026-9082 (Drupal Core SQL Injection) Affected Component: Drupal Core (handling of specific API endpoints or form inputs—specific module logic varies by patch, but Core is impacted). Attack Vector: Network-based, requiring an HTTP request to a vulnerable endpoint. Impact: Confidentiality, Integrity, and Availability impacts. Attackers can execute arbitrary SQL queries against the backend database. In typical Drupal deployments leveraging MySQL or PostgreSQL, this leads to credential theft (admin hashes), data exfiltration, and ultimately, server takeover via web shell upload if database write access is achieved.

Exploitation Mechanics

SQL Injection remains one of the most prolific web vulnerabilities. In this specific instance, a failure to sanitize user-supplied input within a core Drupal module allows an unauthenticated attacker to manipulate the underlying SQL query structure.

Attack Chain:

1. Reconnaissance: Scanners identify Drupal version or fingerprint the site via HTTP headers and generator tags.
2. Probe: Attacker sends crafted HTTP payloads (e.g., UNION SELECT, stacked queries) to the vulnerable endpoint.
3. Exploitation: The database executes the malicious SQL.
4. Objectives:
   • Data Extraction: Dumping the users_field_data table to obtain admin credentials.
   • Privilege Escalation: Modifying session tokens or user roles.
   • Persistence: Using INTO OUTFILE (if permissions allow) to write a webshell (PHP) to the web root, achieving RCE.

Exploitation Status

• In-the-wild: Confirmed Active Exploitation (per CISA KEV).
• Patch Availability: Patches are expected to be released by the Drupal Security Team immediately following disclosure. Updates to Drupal Core 9.x, 10.x, and 11.x are required.

Detection & Response

Detecting SQLi often requires analyzing web application logs (WAF, Apache/Nginx) for anomalies or monitoring the operating system for the effects of exploitation (webshell activity).

The following detection rules target the initial web attack vector and the common follow-on behavior of webshell execution on Linux hosts.

---
title: Potential SQL Injection Attack on Drupal Core
id: 8a4b2c1d-9e6f-4a3b-8c7d-1e2f3a4b5c6d
status: experimental
description: Detects generic SQL injection patterns often used in automated exploits against Drupal and other CMS platforms. Focuses on common SQLi syntax in URI query strings.
references:
  - https://www.cisa.gov/news-events/alerts/2026/05/22/cisa-adds-one-known-exploited-vulnerability-catalog
author: Security Arsenal
date: 2026/05/23
tags:
  - attack.initial_access
  - attack.t1190
  - cve.2026.9082
logsource:
  category: web
  product: apache
detection:
  selection_keywords:
    cs_uri_query|contains:
      - 'UNION SELECT'
      - 'OR 1=1'
      - 'AND 1=1'
      - 'ORDER BY 1--'
      - 'SLEEP(5)'
      - 'WAITFOR DELAY'
  selection_drupal_specific:
    cs_uri_query|contains:
      - 'q=node/'
      - '/user/login'
      - '/form/'
  condition: all of selection_*
falsepositives:
  - Legitimate application testing (rare in production)
level: high
---
title: Linux Web Server Spawning Shell via Webapp
id: 9b5c3d2e-0f7a-5b4c-9d8e-2f3a4b5c6d7e
status: experimental
description: Detects Apache or Nginx web server processes spawning a shell (bash/sh), which is a strong indicator of successful Remote Code Execution or SQLi-to-RCE exploitation.
references:
  - https://attack.mitre.org/techniques/T1059/004/
author: Security Arsenal
date: 2026/05/23
tags:
  - attack.execution
  - attack.t1059.004
  - cve.2026.9082
logsource:
  category: process_creation
  product: linux
detection:
  selection_parent:
    ParentImage|contains:
      - '/apache2'
      - '/httpd'
      - '/nginx'
  selection_child:
    Image|endswith:
      - '/bash'
      - '/sh'
      - '/zsh'
      - '/python'
  condition: all of selection_*
falsepositives:
  - Legitimate administrative CGI scripts (rare)
level: critical

KQL (Microsoft Sentinel / Defender)

Hunt for SQLi signatures in your WAF or Proxy logs (CommonSecurityLog) or Syslog ingested web access logs.

// Hunt for SQL Injection patterns in web traffic
let SQLiKeywords = dynamic(["UNION%20SELECT", "OR%201%3D1", "AND%201%3D1", "ORDER%20BY%201--", "SLEEP(", "WAITFOR%20DELAY", "'--", "'OR"]);
CommonSecurityLog
| where isnotempty(RequestURL)
| extend URLParts = split(RequestURL, "?")
| extend QueryString = iff(array_length(URLParts) > 1, URLParts[1], "")
| where QueryString has_any (SQLiKeywords)
| project TimeGenerated, DeviceName, SourceIP, DestinationIP, RequestURL, RequestMethod, ApplicationProtocol
| summarize count() by SourceIP, RequestURL, bin(TimeGenerated, 5m)
| order by count_ desc

Velociraptor VQL

Hunt for suspicious PHP processes on the endpoint, which may indicate a webshell uploaded after exploiting the SQLi vulnerability.

-- Hunt for PHP processes executing shell commands or eval strings
SELECT Pid, Ppid, Name, Username, StartTime, CommandLine, Exe
FROM pslist()
WHERE Name =~ 'php'
  AND (
    CommandLine =~ 'eval' OR
    CommandLine =~ 'base64_decode' OR
    CommandLine =~ 'shell_exec' OR
    CommandLine =~ 'system' OR
    CommandLine =~ 'passthru'
  )

Remediation Script (Bash)

This script checks for the presence of Drupal and verifies the current version against the patched release. Note: Update the REQUIRED_VERSION variable based on the official Drupal Security Advisory release numbers for CVE-2026-9082.

#!/bin/bash

# Drupal CVE-2026-9082 Remediation & Check Script
# USAGE: sudo ./check_drupal_cve.sh /path/to/drupal/root

DRUPAL_ROOT="$1"
REQUIRED_VERSION="10.4.2" # EXAMPLE: Update this to the actual patched version
LOG_FILE="/var/log/drupal_security_audit.log"

echo "Starting Drupal Security Audit for CVE-2026-9082" | tee -a "$LOG_FILE"

if [ -z "$DRUPAL_ROOT" ]; then
  echo "Error: No Drupal root path provided."
  exit 1
fi

# Check if Drupal is installed
if [ ! -f "$DRUPAL_ROOT/core/lib/Drupal.php" ]; then
  echo "Drupal core not found at $DRUPAL_ROOT."
  exit 1
fi

# Attempt to get version using Drush if available
if command -v drush &> /dev/null; then
  echo "Using Drush to check version..."
  cd "$DRUPAL_ROOT" || exit
  CURRENT_VERSION=$(drush status --format= | grep -oP '"drupal-version"\s*:\s*"\K[^"]+')
else
  # Fallback to reading from core/lib/Drupal.php
  echo "Drush not found, checking core file..."
  CURRENT_VERSION=$(grep -oP 'const VERSION \= \'\K[0-9.]+' "$DRUPAL_ROOT/core/lib/Drupal.php")
fi

echo "Current Drupal Version: $CURRENT_VERSION" | tee -a "$LOG_FILE"
echo "Required Patched Version: $REQUIRED_VERSION" | tee -a "$LOG_FILE"

# Version comparison logic (simplified for example)
if [ "$CURRENT_VERSION" != "$REQUIRED_VERSION" ]; then
  echo "[!] VULNERABLE: Drupal version is below the patched release." | tee -a "$LOG_FILE"
  echo "[!] ACTION REQUIRED: Apply updates immediately via 'composer update drupal/core' or 'drush up'" | tee -a "$LOG_FILE"
  # Check for common webshell indicators in sites/default/files
  echo "[*] Checking for common webshell filenames..."
  find "$DRUPAL_ROOT/sites/default/files" -name "*.php" -type f >> "$LOG_FILE" 2>/dev/null
  if [ -s "$LOG_FILE" ]; then
    echo "[!] WARNING: PHP files found in the files directory. Investigate immediately."
  fi
else
  echo "[+] SECURE: Drupal is patched against CVE-2026-9082."
fi

echo "Audit complete. Log saved to $LOG_FILE"

Remediation

1. Patch Immediately: Apply the latest security updates to Drupal Core. This is the only 100% effective remediation.
   • If using Composer: Run composer update drupal/core -w (with the appropriate version constraint).
   • If using Drush: Run drush up.
2. Verify Patching: Run the Bash script provided above or manually inspect core/lib/Drupal.php to confirm the version constant matches the patched release.
3. Review Access Logs: Scan Apache/Nginx access logs from the past 30 days for the SQLi patterns identified in the Detection section. Look for successful HTTP 200 or 500 (error-based SQLi) responses to these requests.
4. Assess Compromise: If exploitation is confirmed in logs (or if webshells were found):
   • Assume the database is compromised. Force reset all user passwords, especially for administrators.
   • Rotate database credentials stored in settings.php.
   • Review the users_field_data table for unauthorized new accounts or role changes.
5. WAF Configuration: Update your Web Application Firewall (WAF) rules to block the specific request patterns associated with this vulnerability.

Deadlines: Per CISA BOD 22-01, FCEB agencies must remediate this vulnerability by the due date specified in the KEV entry (typically within weeks of KEV addition). Private sector organizations should treat this as an emergency patch.

Related Resources

Security Arsenal Penetration Testing Services AlertMonitor Platform Book a SOC Assessment vulnerability-management Intel Hub