CVE-2026-76460

This flaw acts like a “front door” that can be tricked into thinking an attacker is already allowed in. If someone can reach the vulnerable web/admin endpoint from the network, they may be able to open the device’s admin interface without a real login and then change settings or harm your services.

This matters if your business runs Cisco Identity Services Engine (or the Cisco ISE passive identity connector) and the management interface/API is reachable from a network an attacker could access. The risk is highest because exploitation is confirmed and the vulnerability does not require authentication. Only a risk if the affected device’s vulnerable endpoint is reachable from your network (and especially if it’s reachable from the internet or from untrusted network segments).

This is RED because attackers are already exploiting the authentication bypass in the wild, and Cisco released emergency patches. The CISA KEV listing also assigns a near-term remediation deadline (2026-09-19), so you should treat this as an active, time-sensitive compromise risk.

1. Confirm exposure

• Identify whether you run any of the affected products: identity services engine, identity services engine passive identity connector, cisco identity services engine software, cisco ise passive identity connector.
• Confirm where the web management interface/API is reachable from:
  • Are you exposing it to the internet?
  • Is it reachable from “untrusted” network segments (guest Wi‑Fi, contractor networks, flatter-than-necessary internal networks)?
• If it’s reachable in default/typical setups, assume risk is present until proven otherwise.

2. Check for signs of active exploitation

• Follow Cisco’s emergency guidance and review access logs for suspicious admin activity (the reporting specifically calls out reviewing access.log for suspicious usernames).
• Look for:
  • Requests to management endpoints that occur without legitimate admin login patterns
  • Unusual bursts of attempts or new/odd session behaviors around admin pages

3. Mitigate per vendor/CISA guidance

• The provided patch information does not include a fixed version or upgrade target, so do not wait for a “known fixed release” based on this data.
• Apply mitigations in accordance with vendor instructions.
• Follow CISA KEV requirements listed for this issue, including:
  • Ensuring compliance with CISA’s BOD 26-04 guidance
  • Following CISA “Forensics Triage Requirements”
• If mitigations are unavailable or cannot be applied promptly:
  • Evaluate whether to discontinue use of the product (CISA guidance indicates stakeholders should do so when mitigations can’t be applied).
  • Immediately restrict network reachability so the vulnerable endpoint is not reachable from untrusted networks.

4. Timeline

• CISA remediation due date for this KEV entry is 2026-09-19.

5. After mitigation

• Continue monitoring logs for continued suspicious access attempts.
• Verify that management access now requires proper authentication flows and that unauthorized access patterns cease.

CVE-2026-76460 is a high-impact authentication bypass (CWE-648) affecting Cisco Identity Services Engine and related passive identity connector components. The mechanism is insufficient authentication control on a specific API/endpoint backing the web-based management interface: an attacker on the network can send a crafted request without authentication and gain unauthorized access to the admin interface.

Exploitation status: The vulnerability is listed in CISA KEV (added 2026-09-16) with confirmed real-world exploitation, and exploitation has been reported in the news as “active exploitation.” Public exploits are available, and Cisco issued emergency patches.

Patch availability: The provided patch information does not include fixed versions or upgrade guidance, so remediation relies on Cisco’s emergency mitigations and/or compensating controls such as strict network access restriction as directed by vendor and CISA.