CVE-2026-76451 Overview
CVE-2026-76451 is an SQL and Hibernate Query Language (HQL) injection vulnerability affecting Cisco Identity Services Engine (ISE) and Cisco ISE Passive Identity Connector (ISE-PIC). The flaw exists in affected APIs that fail to properly validate user-supplied input before constructing database queries. An authenticated remote attacker with valid administrative credentials can send crafted requests to execute arbitrary SQL or HQL queries against the underlying database. Successful exploitation allows unauthorized viewing or modification of data. Cisco disclosed the issue in the Cisco Security Advisory: Multi-SQL Injection.
Critical Impact
Authenticated administrators can execute arbitrary SQL or HQL queries to read or modify data outside their authorization boundary on Cisco ISE deployments.
Affected Products
- Cisco Identity Services Engine (ISE)
- Cisco ISE Passive Identity Connector (ISE-PIC)
- Affected API endpoints exposed by the ISE administrative interface
Discovery Timeline
- 2026-09-16 - CVE-2026-76451 published to NVD
- 2026-09-16 - Last updated in NVD database
Technical Details for CVE-2026-76451
Vulnerability Analysis
The vulnerability resides in multiple API endpoints within Cisco ISE and ISE-PIC that accept user-supplied parameters and incorporate them directly into database queries. Because the affected APIs do not sanitize or parameterize input, attackers can inject SQL or HQL syntax into request parameters. The injected query executes with the privileges of the ISE database context, bypassing application-layer access controls that normally restrict administrative data views. Exploitation requires valid administrative credentials, which raises the exploitation bar but does not eliminate risk from compromised or malicious insider accounts. This class of flaw is tracked under CWE-564: SQL Injection: Hibernate.
Root Cause
The root cause is insufficient input validation on affected API parameters before those values are concatenated into SQL or HQL query strings. Safe patterns such as prepared statements or parameterized Hibernate queries are not consistently applied across the affected endpoints. This design gap allows attacker-controlled strings to alter query structure rather than be treated as literal data.
Attack Vector
Exploitation occurs over the network against the ISE administrative API. An attacker authenticates using valid administrative credentials, then submits a crafted request containing SQL or HQL metacharacters within targeted parameters. The affected service parses the injected fragment and executes attacker-controlled query logic against the ISE database. Impact is limited to data integrity and confidentiality within the ISE datastore; the advisory does not indicate availability impact or remote code execution.
No verified public proof-of-concept code is available. For technical parameter-level details, refer to the Cisco Security Advisory: Multi-SQL Injection.
Detection Methods for CVE-2026-76451
Indicators of Compromise
- Unexpected SQL or HQL metacharacters (single quotes, --, UNION, SELECT, FROM) within ISE administrative API request parameters
- Administrative API requests originating from unusual source addresses or outside change-window hours
- Database query errors or Hibernate exceptions logged by ISE following crafted API calls
- Unauthorized modification of ISE policy, endpoint, or identity records without a matching change-management ticket
Detection Strategies
- Enable and forward ISE administrative and API audit logs to a centralized analytics platform for query pattern review
- Alert on API responses containing database error strings or stack traces referencing Hibernate
- Baseline normal administrator API usage and flag deviations in parameter length, encoding, or syntax
- Correlate administrative logins with subsequent bulk data reads from the ISE datastore
Monitoring Recommendations
- Ingest ISE syslog and API audit events into a SIEM for continuous review
- Monitor administrative account activity for privilege misuse or credential sharing
- Track configuration drift on ISE nodes to detect unauthorized changes to policy tables
How to Mitigate CVE-2026-76451
Immediate Actions Required
- Apply the fixed Cisco ISE and ISE-PIC software releases listed in the Cisco Security Advisory as soon as maintenance windows allow
- Rotate administrative credentials and enforce multi-factor authentication on all ISE administrative accounts
- Restrict administrative API access to a small set of trusted management workstations using network access controls
- Review recent administrative activity logs for evidence of anomalous queries or data changes
Patch Information
Cisco has published fixed software versions and remediation guidance in the Cisco Security Advisory: Multi-SQL Injection. Administrators should consult the advisory for the specific fixed release matching their deployed ISE or ISE-PIC train and follow the documented upgrade procedure.
Workarounds
- Cisco has not published a supported workaround; upgrading to a fixed release is the required remediation
- Reduce exposure by limiting the number of accounts with administrative privileges on ISE
- Segment the ISE management plane onto a dedicated administrative network reachable only through jump hosts
- Enable detailed API audit logging so any exploitation attempts prior to patching can be reconstructed
Disclaimer: This content was generated using AI. While we strive for accuracy, please verify critical information with official sources.
