CVE-2021-42131

What it actually does

CVE-2021-42131 is a SQL injection vulnerability in Ivanti Avalanche versions before 6.3.3 affecting access to the Inforail Service. An authenticated or otherwise low-privileged attacker who can reach the vulnerable service can inject crafted SQL into backend database queries, allowing unauthorized manipulation of database logic. Because the vulnerability is associated with privilege escalation and carries high confidentiality, integrity, and availability impact, successful exploitation may allow access to sensitive data, modification of application state, creation or alteration of privileged records, and potentially disruption of Avalanche management functions.

Why it matters to the business

Ivanti Avalanche is commonly used to manage mobile and warehouse/industrial devices, so compromise can affect device management, operational continuity, and trust in managed endpoints. Exploitation could allow an attacker with limited access to elevate privileges, alter management data, access sensitive operational information, or disrupt device administration workflows. The high CVSS score and elevated EPSS probability indicate meaningful exploitation risk even though it is not currently listed in CISA KEV and no ransomware association is noted.

How an attack unfolds

An attacker first obtains low-privileged access or network reachability to the Ivanti Avalanche Inforail Service. They then identify a vulnerable request path or parameter that is incorporated into SQL statements without proper sanitization. By submitting specially crafted SQL syntax, the attacker changes the intended database query behavior. Depending on database permissions and application logic, the attacker may enumerate data, modify user or role records, escalate privileges within Avalanche, alter managed-device configuration data, or cause service disruption through destructive or resource-intensive queries. After privilege escalation, the attacker may use the newly gained access to manage devices, persist via application-level accounts or configuration changes, and conceal activity by modifying database-backed logs or records where possible.

How to fix it

Upgrade Ivanti Avalanche to version 6.3.3 or later. If immediate upgrade is not possible, restrict network access to the Inforail Service to trusted administrative networks only, enforce least-privilege access for Avalanche users and service accounts, place the service behind appropriate firewall/VPN controls, and monitor for suspicious SQL error patterns or privilege changes. Review Ivanti advisories and release notes for any additional hardening steps, database credential rotation recommendations, or post-upgrade validation guidance.

How to confirm the fix worked

Confirm the deployed Ivanti Avalanche version is 6.3.3 or later across all instances. Verify that the Inforail Service is not exposed to untrusted networks and that only authorized administrators can reach it. Review application and database logs for SQL syntax errors, unexpected conditional queries, privilege or role changes, abnormal access to user/device tables, and unusual administrative actions before and after patching. Where permitted, use an authenticated vulnerability scanner or vendor-supported assessment method to confirm the SQL injection is no longer reproducible.

Typical attack path

1. Gain low-privileged access to, or authenticated reachability of, the Ivanti Avalanche Inforail Service.
2. Probe service endpoints or parameters for SQL injection behavior using benign SQL metacharacters or conditional expressions.
3. Send crafted SQL payloads that alter backend query logic.
4. Enumerate database content relevant to users, roles, sessions, device records, or application configuration.
5. Modify database records to elevate privileges or grant additional access within Avalanche.
6. Use elevated Avalanche access to change configurations, access sensitive management data, or disrupt device-management operations.
7. Attempt to remove or alter evidence in application/database records if sufficient privileges are obtained.

How to detect it

To determine whether exploitation already occurred, review Ivanti Avalanche application logs, Inforail Service logs, web/API access logs, database audit logs, Windows Event Logs on the Avalanche server, and any reverse proxy or firewall logs in front of the service. Look for requests containing SQL metacharacters, boolean-based or time-based SQL injection patterns, repeated database errors, unusual access to Inforail endpoints, and abnormal sequences of failed then successful requests. Correlate these events with privilege escalations, new or modified administrative accounts, unexpected role assignments, changes to managed-device records, and service instability. Database logs should be checked for syntax errors, stacked query attempts, unusual UNION SELECT activity, sleep/delay functions, metadata enumeration, and unauthorized UPDATE/INSERT statements affecting users, roles, sessions, or configuration. Because no public exploit maturity or named threat actor is provided, focus detection on generic SQL injection tradecraft and post-exploitation privilege changes rather than actor-specific infrastructure.

• ' OR '1'='1
• " OR "1"="1
• OR 1=1
• UNION SELECT
• UNION ALL SELECT
• information_schema
• sys.tables
• xp_cmdshell
• WAITFOR DELAY
• SLEEP(
• BENCHMARK(
• SQL syntax
• ODBC SQL Server Driver
• SQLException
• SqlException
• Incorrect syntax near
• Unclosed quotation mark after the character string
• The multi-part identifier could not be bound
• Invalid column name
• Conversion failed when converting
• Inforail Service

What your security team should do

• Prioritize upgrading Ivanti Avalanche to 6.3.3 or later because the vulnerability has high impact and a significant EPSS score.
• Immediately restrict access to the Inforail Service to trusted administrative sources until patching is complete.
• Inventory all Ivanti Avalanche deployments, including legacy or test instances, and verify version and exposure status.
• Review Avalanche users, roles, service accounts, and recent privilege changes for unauthorized modifications.
• Search application, web, service, and database logs for SQL injection attempts and suspicious database errors.
• Rotate credentials associated with Avalanche and its backend database if exploitation is suspected.
• Enable or increase logging for authentication events, administrative changes, database errors, and service access.
• Perform post-remediation validation using vendor guidance or authenticated vulnerability scanning.