CVE-2026-20247 Overview
CVE-2026-20247 is a SQL injection vulnerability in Cisco Identity Services Engine (ISE). An unauthenticated remote attacker can send a crafted request to an affected device and modify data in the underlying database. The flaw stems from improper validation of user-supplied input [CWE-89].
The vulnerability is exploitable over the network without authentication or user interaction. Cisco published a security advisory tracking the issue on the Cisco Security Advisories portal.
Critical Impact
Unauthenticated remote attackers can inject SQL statements to modify data stored in the Cisco ISE database, impacting integrity of policy, identity, and access control records.
Affected Products
- Cisco Identity Services Engine (ISE)
- Refer to the Cisco Security Advisory for the definitive list of affected releases
- Deployments exposing the ISE management or policy service interfaces to untrusted networks
Discovery Timeline
- 2026-09-16 - CVE-2026-20247 published to NVD
- 2026-09-16 - Last updated in NVD database
Technical Details for CVE-2026-20247
Vulnerability Analysis
Cisco ISE fails to properly validate user-supplied input before incorporating it into SQL statements executed against the backend database. An attacker crafts an HTTP request containing malicious SQL syntax and sends it to a vulnerable endpoint on the ISE device. The application concatenates the untrusted input into a query, and the database executes the attacker-controlled statement.
The impact is scoped to integrity of the underlying database. A successful exploit allows modification of data, but the advisory does not describe direct confidentiality loss or denial-of-service outcomes. Because Cisco ISE stores authentication policies, endpoint identities, network device credentials references, and authorization rules, tampering with database records can undermine network access control decisions across the environment.
Exploitation requires no authentication and no user interaction. The attack occurs over the network against exposed ISE service endpoints.
Root Cause
The root cause is improper neutralization of special elements used in an SQL command [CWE-89]. User-supplied parameters reach the SQL execution layer without parameterized queries or sufficient sanitization. Any input path handling attacker-controlled data becomes a candidate injection vector.
Attack Vector
The attack vector is network-based. An attacker with reachability to the affected ISE service sends a crafted request containing SQL metacharacters or statement fragments. No prior credentials, session, or victim interaction are needed. Cisco has not disclosed the specific vulnerable endpoint or parameter in the public advisory summary.
No public proof-of-concept exploit code is available, and this CVE is not listed in the CISA Known Exploited Vulnerabilities catalog at publication.
Detection Methods for CVE-2026-20247
Indicators of Compromise
- HTTP requests to ISE administrative or policy service endpoints containing SQL metacharacters such as single quotes, UNION, SELECT, --, or ;
- Unexpected modifications to ISE policy, endpoint, or identity database records without a corresponding administrative audit trail
- Anomalous authentication or authorization decisions correlating with unusual inbound requests to ISE
Detection Strategies
- Inspect web server and application logs on ISE nodes for request patterns matching known SQL injection payloads
- Correlate ISE database change events with administrator session logs to identify unauthorized modifications
- Deploy signatures on network intrusion detection systems for SQL injection payloads targeting ISE HTTP interfaces
Monitoring Recommendations
- Forward ISE syslog, admin audit, and web access logs to a centralized analytics platform for query and correlation
- Alert on requests from non-management network segments reaching ISE service ports
- Baseline normal request patterns to ISE APIs and flag statistical deviations in URI, parameter, or payload structure
How to Mitigate CVE-2026-20247
Immediate Actions Required
- Review the Cisco Security Advisory and identify affected ISE versions in your environment
- Apply the fixed software release provided by Cisco as soon as feasible
- Restrict network access to ISE management and policy service interfaces to trusted administrative networks only
- Audit the ISE database for unexpected changes to policy, identity, and endpoint records
Patch Information
Cisco has published a security advisory for this SQL injection issue. Consult the advisory cisco-sa-ise-sql-inj-3QTKR947 for the list of fixed releases and upgrade guidance. Apply the vendor-provided patched version rather than attempting configuration-only workarounds.
Workarounds
- Place ISE administrative and API interfaces behind a management VLAN or jump host reachable only from authorized operator subnets
- Enforce access control lists on upstream firewalls and switches to block untrusted sources from reaching ISE service ports
- Deploy a web application firewall in front of ISE web interfaces to filter SQL injection payloads until patching is complete
- Increase logging verbosity on ISE and forward events to a monitoring platform to detect exploitation attempts
Disclaimer: This content was generated using AI. While we strive for accuracy, please verify critical information with official sources.
